Glossary

268 terms defined in plain English. Each one links to the latest coverage in the index, and to the tools and guides that use it.

A

AAFCO: The US body that sets model pet food rules and nutrient profiles but does not itself approve, test or certify any dog food.

Addison's disease: A hormone disease in which the adrenal glands make too little cortisol and often too little aldosterone, causing vague illness and sometimes crisis.

Adoption fee: The payment a shelter or rescue asks when you adopt a dog, helping cover vet care and running costs, often including vaccines, spay or neuter and a microchip.

Airline pet carrier: A carrier that meets an airline's size and construction rules for a dog travelling in the cabin under a seat, or in a larger hard crate in the hold.

Anal sacs: Two scent pouches beside a dog's anus that can become full, infected or blocked, causing scooting and licking.

Anesthesia: A medically induced, controlled loss of consciousness for surgery, dental cleaning or imaging, with monitoring throughout.

Animal shelter: A facility that houses stray, lost and surrendered dogs and cats, run by a city, county or non-profit, which returns pets to owners or places them in new homes.

Assistance dog: A broad term for a dog trained to help a person with a disability, including guide, hearing and service dogs; wider than the ADA term service animal.

Atopic dermatitis: An inherited tendency to develop itchy skin and ear disease from allergens in the environment such as pollen, dust mites and molds.

Aversive: Anything a dog wants to avoid, from a leash pop or shock to a loud noise, when used to change behavior.

B

Backyard breeder: A person who breeds dogs casually, usually without health testing, breed knowledge or a plan for the puppies; not a puppy mill, but often a poor source.

Barking: A dog's most common vocal signal, used to alert, greet, demand, play or express fear, frustration or loneliness.

Basic obedience: The core manners most pet dogs are taught, usually sit, down, stay, come, walking nicely on a leash and leave it.

Best in Show: The top award at an all-breed dog show, given to the dog chosen from the seven group winners as the best example of its breed.

Biopsy: The removal of a small piece of tissue, or a sample of cells, for examination under a microscope to find out what a lump or abnormal tissue is.

Bite inhibition: A dog's learned ability to control the force of its mouth, which puppies normally acquire through play with littermates and people.

Bloat (GDV): A life-threatening emergency in which a dog's stomach swells with gas and may twist, cutting off blood flow and breathing.

Blood panel: A set of blood tests that counts blood cells and measures organ-related chemicals, used to screen healthy dogs and investigate illness.

Body condition score: A hands-on rating of how lean or fat a dog is on a 9-point scale, more reliable than weight alone, with 4 or 5 as ideal.

Brachycephalic: Having a short, broad skull and flattened muzzle, as in the Pug, Bulldog and French Bulldog, which can narrow the airway and affect breathing and cooling.

Brachycephalic obstructive airway syndrome: A set of airway abnormalities in flat-faced breeds that make breathing hard, causing noisy breathing, poor heat tolerance and collapse.

Breed standard: The written description of an ideal dog of a breed, covering size, proportions, coat, colour, movement and temperament, used to judge dogs and guide breeding.

Breed-specific legislation: A law that bans or restricts dogs by breed or appearance, such as pit bull type dogs, rather than by what an individual dog has done.

Brindle: A coat pattern of dark, tiger-like stripes over a lighter base of tan, fawn or red, seen in Boxers, Greyhounds, Bulldogs and many others.

C

Calming signals: Subtle behaviors such as yawning, turning away and sniffing that dogs are said to use to ease tension and avoid conflict.

Calorie: The unit of energy in food; dog food labels list kilocalories per cup or kilogram, which is how portions and weight are controlled.

Canine cognitive dysfunction: A brain aging disorder in older dogs, similar to dementia, that causes disorientation, sleep changes and loss of learned habits.

Canine distemper: A serious, vaccine-preventable virus that attacks a dog's respiratory, digestive and nervous systems, and spreads through the air.

Canine Good Citizen: An American Kennel Club program and ten-item test that rewards well-mannered dogs with a certificate.

Canine parvovirus: A highly contagious, often deadly virus that attacks the gut and bone marrow, mainly in unvaccinated puppies, and is preventable by vaccination.

Capturing: Marking and rewarding a behavior the dog offers on its own, such as sitting or lying down, so that it happens more often.

Cataracts: Cloudiness in the lens of the eye that blocks light and can lead to blindness, often inherited or linked to diabetes.

Certified applied animal behaviorist: A behavior specialist certified by the Animal Behavior Society, normally holding a doctorate and years of experience, who treats behavior problems.

Cherry eye: A red, swollen lump at the inner corner of the eye caused when the gland of the third eyelid pops out of place.

Chewing: A normal behavior in which dogs gnaw on objects to explore, relieve teething, relax or burn off energy.

Chocolate toxicity: Poisoning from the theobromine and caffeine in chocolate, which is more dangerous the darker the chocolate and the smaller the dog.

Chronic kidney disease: A gradual, permanent loss of kidney function that causes increased thirst and urination, weight loss and poor appetite, mainly in older dogs.

Classical conditioning: Learning that links two events so that a dog reacts to a signal in the same way it reacts to what the signal predicts.

Clicker training: A reward-based method in which a small device makes a click at the instant a dog does the right thing, followed by a treat.

Complete and balanced: A label claim that a dog food contains every nutrient a dog needs, in the right amounts, for the life stage named on the package.

Conformation: A dog show event in which each purebred dog is judged on how closely its structure and movement match its written breed standard.

Core vaccines: The vaccines veterinary guidelines recommend for virtually every dog, protecting against distemper, parvovirus, canine adenovirus and rabies.

Counter surfing: A dog's habit of putting its feet or nose on kitchen counters or tables to take food, kept going because every success is rewarded.

Crate training: Teaching a dog to treat a crate as a safe, comfortable place to rest, used for house training, travel and recovery.

Critical socialization period: The early weeks of a puppy's life, roughly 3 to 12 weeks, when it learns most easily to accept new people, animals and places.

Cruciate ligament tear: A tear of the cranial cruciate ligament, the main stabilizer of the dog's knee, and a leading cause of sudden hind-leg lameness.

Cue: A word, gesture or situation that tells a dog a particular behavior is available and will be rewarded.

Curly coat: A coat of tight curls or waves, as on the Poodle, Bichon Frise and Curly-Coated Retriever, which sheds little but mats without regular grooming.

Cushing's disease: A hormone disorder in which the body makes too much cortisol, usually in middle-aged and older dogs, causing thirst, a pot belly and thin skin.

D

Dangerous dog law: A law that lets authorities declare a dog dangerous after an attack or threat and set conditions for its owner, such as an enclosure, muzzle or insurance.

Deductible: The amount you pay toward covered vet bills before pet insurance begins to reimburse you.

Dental disease: Plaque, tartar and gum infection that damage a dog's teeth and supporting bone; it is the most common health problem vets find in adult dogs.

Desensitization and counter-conditioning: A training plan that exposes a dog to a fear trigger at a level it can handle while pairing it with something good, to change how the dog feels.

Designer breed: A dog deliberately bred from two chosen breeds, often with a catchy name such as Labradoodle or Cockapoo, that is not a recognised breed itself.

Dewclaw: A small extra digit on the inner side of a dog's leg above the paw, found on the front legs of most dogs and on the hind legs of some breeds.

DHPP vaccine: The standard combination puppy and adult shot covering distemper, hepatitis (adenovirus), parainfluenza and parvovirus.

Diabetes mellitus: A disease in which the body cannot make or use enough insulin, so blood sugar stays high, with increased thirst and urination.

Digging: A natural dog behavior of scraping at soil or bedding, done for cooling, hunting, escaping, hiding things or boredom.

Dilated cardiomyopathy: A heart muscle disease in which the heart chambers stretch and the muscle weakens, so the heart pumps poorly; some breeds inherit it.

Dock diving: A sport in which dogs run along a dock and leap into a pool, judged on how far or how high they jump, often chasing a toy.

Dog agility: A timed sport in which a handler directs a dog over an obstacle course of jumps, tunnels, weave poles and ramps, open to purebred and mixed-breed dogs.

Dog boarding: Overnight care for a dog at a kennel, a pet hotel or a private home while its owners travel.

Dog body language: The postures, faces and movements dogs use to communicate feelings and intentions without sound.

Dog breeder: A person who plans and raises litters of puppies; a responsible breeder health tests the parents, follows a breed standard and stays involved with each puppy.

Dog car seat and restraint: A booster seat, harness or secured crate that holds a dog in place in a vehicle, protecting both the dog and the people from injury in a sudden stop or crash.

Dog crate: A box or cage that provides a dog with a safe, enclosed space at home or in a car; it should be large enough to stand, turn and lie down in.

Dog daycare: A daytime service where dogs spend hours supervised in play groups or on their own, an option for owners who are at work.

Dog DNA test: A cheek-swab or blood test that analyses a dog's genes to estimate its breed mix, check for inherited disease variants or identify certain traits.

Dog door: A flap or panel set in a door or wall that lets a dog go in and out of the house on its own.

Dog food recall: The removal of a dog food from sale and homes because of a safety problem such as contamination, toxins or a nutrient error.

Dog groomer: A professional who bathes, brushes, clips and trims dogs, in a salon, a mobile van or a clinic.

Dog license: A local government registration of a dog, often required by law, usually needing proof of rabies vaccination and giving a tag that helps return a lost dog.

Dog park: A public fenced area where dogs can play off leash, usually with separate sections for small and large dogs and rules for owners.

Dog rescue: A non-profit or volunteer group that takes in dogs from shelters, owners or the street and places them in new homes, often through foster homes.

Dog stroller: A wheeled carrier that lets you push a small, older or injured dog, designed for dogs that cannot walk far, not as a replacement for exercise.

Dog vision: How dogs see, which is less sharp than people, with a limited range of colors, but better in low light and at spotting movement.

Dog walker: A person paid to take a dog out for exercise and toilet breaks while the owner is away, either one-on-one or in a group.

Dolichocephalic: Having a long, narrow skull and a long muzzle, as in the Greyhound, Collie, Borzoi and Saluki.

Dominance: A term that properly describes a relationship in which one animal gets priority over a resource, not a personality trait or a reason for a dog's behavior.

Double coat: A coat with two layers, a soft dense undercoat beneath longer, coarser guard hairs, that insulates a dog against cold and heat and sheds heavily in season.

Drop it: A cue that asks a dog to let go of something in its mouth, taught as a trade rather than a struggle.

Dry eye: A condition in which a dog does not make enough tears, leaving the eye sore, red and covered with sticky discharge.

Dry matter basis: A way of comparing dog foods by removing the water from their labeled nutrient percentages so wet and dry foods can be compared fairly.

E

E-collar: A remote-controlled collar that delivers a tone, vibration or electric stimulation to a dog, and is a debated training tool.

Ear infection: Inflammation of the outer ear canal, often with yeast or bacteria, causing head shaking, scratching, odor and pain.

Earthdog: A test in which small terriers and Dachshunds follow a scent through a tunnel to reach a caged quarry, showing their instinct to hunt underground.

Elbow dysplasia: A group of developmental problems in the elbow joint that cause front-leg lameness, usually starting in young, fast-growing large-breed dogs.

Emotional support animal: An animal that comforts a person with a disability but is not task trained; protected in housing but not given public access under the ADA.

Enrichment: Giving a dog chances to use its natural abilities, such as sniffing, chewing, foraging and problem solving, to improve its well-being.

Epilepsy: A brain disorder that causes repeated seizures, most often the inherited kind with no other cause found, usually starting in young adult dogs.

Euthanasia: The humane, painless ending of a dog's life by a veterinarian, chosen to prevent suffering when quality of life can no longer be maintained.

Exercise pen: A freestanding set of hinged panels that forms a portable fenced area for a dog, bigger than a crate and easy to fold away.

Extinction burst: A temporary increase in a behavior, often with more intensity, when a reward that used to follow it is stopped.

F

Fear period: A stage, often described around 8 to 11 weeks and again in adolescence, when a young dog may react strongly to things it once ignored.

Fecal test: A laboratory check of a dog's stool for parasite eggs and organisms such as roundworm, hookworm, whipworm and Giardia.

Fleas: Tiny blood-feeding insects that cause itching, can trigger allergic skin disease and carry tapeworm, and infest the home as well as the dog.

Flyball: A relay sport in which teams of four dogs race over hurdles to a box, catch a ball it releases, and run back to the line, judged on speed and accuracy.

Food allergy: An immune reaction to a protein in the diet that usually causes itchy skin and ear problems, and sometimes digestive upset.

Food intolerance: A non-immune bad reaction to a food, usually showing as vomiting, gas or loose stool, which differs from a true food allergy.

Force-free: A training approach that avoids pain, fear and intimidation and teaches dogs with rewards, patience and good management.

Foster: A temporary home that cares for a dog until it is adopted, which frees kennel space and helps the dog adjust to life in a house.

Foundation Stock Service: An AKC record-keeping program for rare breeds not yet fully recognised, letting breeders register dogs on the way to full recognition.

Free feeding: Leaving food available all day so a dog eats when it likes, as opposed to measured meals at set times.

Fédération Cynologique Internationale: The international federation of national kennel clubs, based in Belgium, that recognises breeds worldwide and assigns each one to a country of origin.

G

Genetic diversity: The variety of genes within a breed or population; closed stud books and heavy use of a few popular sires reduce it and make inherited conditions more common.

Giardia: A microscopic intestinal parasite picked up from contaminated water or feces that can cause soft, greasy diarrhea, mainly in puppies.

Glaucoma: Raised pressure inside the eye that damages the optic nerve; it is painful and can cause permanent blindness within hours or days.

Glucosamine: A supplement, often paired with chondroitin, sold to support joint cartilage; evidence of benefit in dogs is mixed and product quality varies.

GPS dog tracker: A collar-mounted device that uses satellite positioning and a cellular connection to show your dog's location on a phone, usually for a monthly fee.

Grain-free: A dog food made without wheat, corn, rice or other grains, usually replaced by legumes or potatoes; it is not automatically healthier.

Grape and raisin toxicity: Poisoning from grapes, raisins, sultanas and currants that can cause sudden kidney failure in dogs, at amounts that are hard to predict.

Guide dog: A dog trained to lead a person who is blind or has low vision around obstacles and safely through traffic, and one of the oldest kinds of assistance dog.

H

Habituation: A dog's learned reduction of its reaction to something harmless that is met again and again without consequence.

Harness vs collar: A flat collar holds ID tags, while a harness spreads a leash's pull across a dog's chest and shoulders instead of the neck.

Head halter: A strap that fits around a dog's nose and neck so that the leash gently turns its head, used to manage pulling.

Health testing: The screening of breeding dogs for inherited conditions, such as hip, elbow, heart, eye and DNA tests, whose results are shared with buyers.

Hearing range: The span of sound pitches dogs can hear, reaching to about 45,000 Hz compared with roughly 20,000 Hz for people.

Heartworm disease: A serious parasitic disease spread by mosquitoes in which worms grow in a dog's heart and lungs, and which monthly prevention can stop.

Heatstroke: A dangerous rise in body temperature, from about 104 F up, when a dog cannot cool itself, and a true emergency.

Heel: A formal skill in which a dog walks close at its handler's side, matching the handler's pace and turns.

Herding Group: The AKC group of breeds developed to gather, drive and guard livestock, including the Border Collie, German Shepherd Dog and Corgis.

Herding trial: A competition in which a dog gathers, drives and pens livestock such as sheep or cattle under a handler's direction, judged on control and ability.

High-value treat: A food reward the dog finds especially tempting, such as cooked chicken or cheese, saved for difficult training moments.

Hip dysplasia: An inherited, developmental malformation of the hip joint in which the ball and socket fit loosely, leading to wear and arthritis.

Hock: The joint on a dog's hind leg between the lower thigh and the foot, roughly the equivalent of a human ankle, used in judging structure and movement.

Hookworm: A small intestinal worm that attaches to the gut wall and feeds on blood, causing anemia in puppies, and can burrow into human skin.

Hot spot: A fast-appearing, red, wet and painful patch of skin that a dog creates by licking or scratching, usually because of an underlying irritation.

Hound Group: The AKC group of breeds developed to hunt by scent or by sight, from the Beagle and Bloodhound to the Greyhound and Whippet.

House training: Teaching a dog to relieve itself outdoors or in a chosen spot instead of inside the home.

Hydrolyzed protein diet: A veterinary diet whose proteins are chopped into pieces too small for the immune system to recognize, used to diagnose and manage food allergy.

Hypoallergenic dog claim: The marketing claim that a breed will not trigger allergies; no dog is truly hypoallergenic, since allergens also come from saliva, skin and urine.

Hypothyroidism: A condition in which the thyroid gland makes too little hormone, slowing the metabolism and causing weight gain, lethargy and coat and skin changes.

I

IGP (Schutzhund): A three-part working-dog sport of tracking, obedience and protection, formerly Schutzhund and IPO, that began as a breed test for the German Shepherd Dog.

Inbreeding coefficient: A percentage showing how likely a dog is to carry two identical copies of a gene from a shared ancestor, a measure of how closely related its parents were.

Intervertebral disc disease: A spinal condition in which a cushioning disc between vertebrae bulges or bursts and presses on the spinal cord, causing pain or weakness.

J

Jealousy: A jealous-like reaction some dogs show when an owner gives attention to a rival, which researchers still debate how to interpret.

Jumping up: A dog's habit of putting its paws on people when greeting them, usually kept going by the attention it gets.

Junior showmanship: A show competition for young handlers in which the person, not the dog, is judged on how well they present and handle a dog.

K

Kennel cough: A contagious airway infection with a dry, honking cough, caused by several viruses and bacteria and common where dogs gather.

Kennel registry: An organisation that keeps records of dogs and their parentage, issues registration papers and pedigrees, and often runs shows and sports.

Kibble: Dry, cooked, bite-size pieces of dog food, usually made by extrusion, that are shelf-stable, convenient and the most common way to feed dogs.

L

Landrace dog: A local population of dogs shaped by climate, work and natural selection in one region, rather than by a written breed standard and closed stud book.

Leash law: A local or state rule that requires a dog to be on a leash or under control in public, with set exceptions such as designated off-leash areas.

Leash reactivity: Barking, lunging or growling at other dogs or people when on a leash, often from fear or frustration at being unable to move freely.

Leave it: A cue that tells a dog to stop paying attention to something, such as food on the ground, and turn away from it.

Leptospirosis: A bacterial infection spread through the urine of wildlife and contaminated water that can damage a dog's kidneys and liver, and can infect people.

Life stage: The category on a dog food label, such as growth, adult maintenance or all life stages, that shows the nutrient needs the recipe is designed to meet.

Limited-ingredient diet: A food built around one protein and one carbohydrate source to reduce exposure, often used to look for a food allergy.

Lip licking: A quick tongue flick over the lips or nose that, outside mealtimes, often signals a dog is nervous or uncertain.

Loose-leash walking: Walking with a dog beside or near the handler on a slack leash, without the dog pulling.

Lure coursing: A sport in which dogs chase a mechanically pulled lure across a field in a pattern that simulates running prey, mainly for sighthounds.

Luring: A teaching method in which a treat held near the dog's nose guides it into a position, such as sit or down, which is then rewarded.

Luxating patella: A condition in which the kneecap slips out of its groove, common in small breeds and often seen as a brief hop or skip in the stride.

Lyme disease: A bacterial infection spread by blacklegged ticks that causes fever and joint pain in some dogs, and rarely damages the kidneys.

Lymphoma: A cancer of the lymphocytes, a type of white blood cell, that most often appears as firm, painless swelling of lymph nodes.

M

Marker word: A short word, such as "yes", said at the instant a dog does the right thing to tell it a reward is coming.

Martingale collar: A two-loop collar that tightens a limited amount when a dog pulls, so it cannot slip over a narrow head but does not choke when sized correctly.

Mast cell tumor: The most common skin cancer in dogs, which can look like any lump, so every new skin lump should be sampled by a veterinarian.

Merle: A coat pattern with patches of diluted colour on a darker background, seen in breeds such as the Australian Shepherd, Collie and Great Dane.

Microchip and registry: A rice-sized implant that holds an ID number, which links to your contact details only if you register it; it is not a GPS tracker.

Mitral valve disease: A slow wearing of the heart's mitral valve that lets blood leak backward, the most common heart disease in older small-breed dogs.

Mixed breed: A dog whose parents are of different breeds or whose ancestry is unknown, often called a mutt.

Mouthing: A dog's use of its mouth on hands, clothes or people during play or greeting, without intent to injure.

Mushing: Travelling or racing with a team of dogs that pull a sled, cart or rig, from short sprint races to the long-distance Iditarod in Alaska.

N

Negative punishment: Removing something a dog wants right after an unwanted behavior so that the behavior becomes less likely.

Negative reinforcement: Removing something unpleasant when a dog performs a behavior so that the behavior becomes more likely.

Neuter: Surgery that removes a male dog's testicles, preventing breeding and some health problems and sometimes changing certain behaviors.

Noise phobia: An intense, lasting fear of sudden or loud sounds such as thunder, fireworks or gunshots, shown by trembling, hiding or panic.

Non-core vaccines: Vaccines given only to dogs whose lifestyle, location or travel puts them at risk, such as Bordetella, Lyme and canine influenza.

Non-Sporting Group: The AKC group for breeds that fit no other group, a mix of different sizes, coats and histories such as the Poodle, Bulldog and Dalmatian.

Nosework: A dog sport in which dogs search rooms, vehicles, outdoor areas and containers for a specific trained odor and alert their handlers.

Novel protein: A protein source a dog has never eaten before, used in elimination diets because the immune system has not learned to react to it.

O

Obedience trial: A formal dog sport that judges how precisely a dog performs set exercises such as heeling, recalls, stays and retrieves, in classes from Novice to Utility.

Obesity: Excess body fat that shortens lives and raises the risk of arthritis, diabetes and other disease; it is the most common nutrition problem in pet dogs.

Off-leash: When a dog is allowed to move without a leash, legal only in places that permit it, such as fenced dog parks, some trails and private land.

Omega-3 fatty acids: Fats, especially EPA and DHA from fish oil, that may calm inflammation and support skin, joints, heart and brain; the right amount is a vet decision.

One-bite rule: An older legal rule under which an owner is liable for a bite only if the owner knew the dog was dangerous, so in practice the first bite was often free.

Operant conditioning: Learning in which a dog changes its behavior because of the consequences that follow it.

Orthopedic Foundation for Animals: A US non-profit that keeps open databases of health screening results for dogs, including hip and elbow ratings, to help breeders choose healthy parents.

Osteoarthritis: A long-term, painful wearing down of joint cartilage that causes stiffness and reluctance to move, common in older and overweight dogs.

Osteosarcoma: The most common bone cancer in dogs, an aggressive tumor that mainly affects large and giant breeds, often in a front leg.

P

Pack theory: The outdated idea that dogs live in strict wolf-style packs in which an owner must be the alpha to avoid being dominated.

Pancreatitis: Inflammation of the pancreas that causes vomiting, belly pain and loss of appetite, and can range from mild to life-threatening.

Pedigree: A written family tree of a dog showing its ancestors over several generations, usually with registered names, titles and sometimes health results.

PennHIP: A hip screening method that measures joint looseness with a stressed x-ray, reported as a distraction index, and can be done in puppies from 16 weeks.

Pet hospice: Comfort-focused care for a dog with a terminal or very advanced illness, aiming at good days and little pain until the end.

Pet insurance: A policy that reimburses a share of veterinary bills for covered accidents and illnesses in return for a monthly premium.

Pet sitter: A person who looks after a dog in the owner's home, with drop-in visits or overnight stays, so the dog stays in a familiar setting.

Piloerection: The raising of the hair along a dog's neck, shoulders and back, a sign of strong arousal rather than automatic aggression.

Place: A cue that sends a dog to a mat or bed and keeps it there, often used when visitors arrive or meals are served.

Play: Voluntary, energetic and usually social activity that dogs do for fun, including chasing, wrestling, tugging and bowing.

Play bow: A posture in which a dog lowers its front legs and chest while keeping its rear up, signalling an invitation to play.

Pointing comprehension: A dog's ability to follow a human finger point to find hidden food, a skill researchers study to learn how dogs read people.

Police K-9: A dog trained to assist law enforcement, usually in tracking, apprehending suspects and detecting drugs or explosives, working with one handler.

Positive punishment: Adding something unpleasant right after a behavior to make that behavior less likely, such as a leash jerk or a startling noise.

Positive reinforcement: Adding something a dog likes right after a behavior so that the behavior becomes more likely to happen again.

Pre-existing condition: An illness, injury or sign that a dog had before pet insurance began or during the waiting period, and which a policy usually will not cover.

Prescription diet: A food formulated to help manage a medical condition such as kidney disease or food allergy, fed under veterinary supervision.

Probiotics: Live beneficial microorganisms given as supplements or in food that may help some dogs with digestive upset, though products vary a lot.

Progressive retinal atrophy: A group of inherited diseases in which the retina slowly degenerates, causing night blindness first and then total blindness, without pain.

Prong collar: A collar of metal links with blunt prongs that pinch the neck when pulled, used for leash corrections and widely debated.

Puppy kindergarten: An early group class where young puppies learn basic manners and meet other puppies and people in a supervised setting.

Puppy mill: A large-scale breeding operation that puts profit above the welfare of its dogs, producing puppies sold through pet stores, brokers or websites.

Purebred: A dog whose parents and ancestors belong to one recognised breed and are recorded in a registry, so its ancestry can be traced on paper.

Puzzle feeder: A toy or bowl that makes a dog work to get its food, giving it a mental task and slowing down eating.

Pyometra: A life-threatening bacterial infection of the uterus in unspayed female dogs, usually in the weeks after a heat cycle, and a surgical emergency.

Q

Quality of life scale: A scoring tool owners and vets use to judge an ill or elderly dog's comfort and decide when to consider euthanasia.

R

Rabies: A viral disease of the nervous system, spread through bites, that is nearly always fatal once signs appear but is preventable by vaccination.

Rally: A dog sport in which a handler and dog move through a course of numbered signs, each showing an exercise to perform, with talking and encouragement allowed.

Raw feeding: Feeding uncooked meat, organs and often bones, either homemade or commercial, which carries germ risks for dogs and the people who handle it.

Reactivity: A dog's exaggerated reaction, such as barking, lunging or freezing, to a trigger like other dogs, people or noises.

Recall: A dog's trained response to turn and come straight to its owner when called, one of the most important safety behaviors.

Reimbursement rate: The percentage of a covered vet bill that a pet insurer repays after the deductible, often 70, 80 or 90 percent.

Resource guarding: A dog's tendency to protect food, toys, places or people from others by stiffening, growling, snapping or biting.

Roundworm: A common intestinal worm that often infects puppies, frequently from the mother, and can pass to people, especially children.

S

Sable: A coat colour in which each hair is banded or tipped with black over a lighter base, giving a shaded look as in many Collies and German Shepherds.

Scent marking: A dog's deposit of urine, feces or gland scent to leave information for other dogs, not the same as house soiling.

Scent work: Any activity in which a dog uses its nose to find a target odor, from backyard hide-and-seek games to trained detection jobs.

Search and rescue dog: A dog trained to find missing or trapped people by scent, working with a handler in the wilderness, disasters or collapsed buildings.

Senior wellness: A preventive care plan for aging dogs, with more frequent exams and screening tests to catch age-related disease early.

Sense of smell: A dog's main sense, thousands of times more sensitive than ours by some estimates, with far more scent receptors and a dedicated airflow in the nose.

Separation anxiety: Real distress shown by a dog when left alone or away from a particular person, such as howling, destruction, pacing or house soiling.

Service dog: A dog individually trained to do work or perform tasks for a person with a disability, and the only dog with public-access rights under the US ADA.

Shaping: Building a new behavior in small steps by rewarding each step that gets closer to the final goal.

Silky coat: A fine, glossy, flowing coat that tangles easily and needs regular brushing, found on breeds such as the Yorkshire Terrier, Maltese and Afghan Hound.

Smooth coat: A short, close-lying coat that needs little grooming, found on breeds such as the Boxer, Beagle, Greyhound and Doberman Pinscher.

Snuffle mat: A fabric mat with many strips or pockets in which food is hidden so that a dog has to sniff and forage for it.

Social learning: Learning a behavior by watching another dog or a person do it, which dogs can do in some situations.

Socialization: Exposing a young dog to a wide range of people, animals, places and sounds in a positive way so that new things do not frighten it.

Spay: Surgery that removes a female dog's ovaries, and usually the uterus, to prevent pregnancy and heat cycles and eliminate the risk of pyometra.

Spay and neuter in rescues: The common practice of sterilising dogs before or soon after adoption, set by shelter or rescue policy to prevent unplanned litters.

Sporting Group: The AKC group of breeds developed to help hunters find and retrieve game birds, including retrievers, spaniels, pointers and setters.

Stack: The standing pose a show dog holds so a judge can see its structure, set by the handler (hand stack) or held by the dog on its own (free stack).

Stay: A cue that asks a dog to keep its position, such as sitting or lying down, until the owner releases it.

Stress signals: Small changes in behavior, such as panting without heat, yawning, shaking off or a tucked tail, that show a dog is uneasy.

Strict liability for dog bites: A legal rule that makes a dog's owner responsible for a bite injury regardless of whether the owner knew the dog was dangerous.

T

Tail docking and ear cropping: The surgical shortening of a dog's tail and reshaping of its ears for looks; banned or restricted in many countries and opposed by vets when cosmetic.

Tail wagging: A dog's tail movement, which signals arousal and emotion but does not mean a dog is friendly.

Tapeworm: A flat intestinal worm, usually caught by swallowing an infected flea, that sheds rice-like segments seen near a dog's tail.

Targeting: Teaching a dog to touch its nose to a hand or object on cue, a building block for many other skills.

Terrier Group: The AKC group of breeds developed to hunt and kill vermin such as rats, foxes and badgers, usually small to medium, bold and energetic.

Tethering law: A state or local law that limits how and how long a dog may be tied or chained outdoors, to prevent neglect and injury.

Theory of mind: The ability to understand that others have their own knowledge, wishes and beliefs, which research suggests dogs may show only in limited ways.

Therapy dog: A pet that, with its owner, visits hospitals, schools and nursing homes to comfort others; it has no special public-access rights.

Threshold: The point at which a dog goes from noticing something to reacting to it, often described as a distance or an intensity.

Ticks: Blood-feeding arachnids that attach to dogs outdoors and can carry diseases such as Lyme disease, ehrlichiosis and Rocky Mountain spotted fever.

Titer test: A blood test that measures antibodies to a disease, sometimes used to check a dog's immunity to distemper or parvovirus instead of re-vaccinating.

Toy Group: The AKC group of very small companion breeds, such as the Chihuahua, Pomeranian and Pug, kept mainly for company.

Trainer versus behaviorist: A trainer teaches skills and manners, while a behaviorist is trained to assess and treat problems such as fear and aggression.

Travel crate: A sturdy, ventilated crate used to carry or secure a dog in a vehicle or for transport, built to stay closed in a collision.

Trigger stacking: Several stressful events building up in a short time so that a dog that would normally cope reacts strongly to a small extra trigger.

U

Ultrasound: A real-time imaging test that uses sound waves to show a dog's organs, heart and pregnancy without radiation.

Undercoat: The soft, short, dense layer of fur beneath the longer outer guard hairs of a double-coated dog, which provides insulation and is shed in large amounts.

United Kennel Club: A US registry founded in 1898 that registers many working and hunting breeds and also runs sports, with its own breed groups and standards.

V

Veterinary specialist: A veterinarian who completed extra years of training and exams in one field, such as cardiology or oncology, and sees dogs on referral.

Vomeronasal organ: A small scent-sensing organ in the roof of a dog's mouth and nose that detects chemical signals such as pheromones.

W

Waiting period: The time after a pet insurance policy starts, often a few days to several months, during which some or all claims are not covered.

Wellness exam: A routine, nose-to-tail check-up of a healthy dog that updates vaccines, screens for hidden problems and tracks weight over time.

Westminster Kennel Club Dog Show: The Westminster Kennel Club Dog Show, held in New York since 1877, is the best-known US conformation show and ends with a Best in Show award.

Whale eye: A look in which a dog turns its head away but keeps its eyes on something, showing a crescent of white, and is often uneasy.

Whipworm: A parasite of the large intestine whose eggs stay in soil for years and which can cause chronic, mucus-covered diarrhea in dogs.

Wire coat: A harsh, bristly outer coat with a dense undercoat, found on many terriers and some gundogs, traditionally kept tidy by hand stripping.

Withers: The ridge between a dog's shoulder blades at the base of the neck, the standard point from which a dog's height is measured.

Working Group: The AKC group of larger breeds developed for jobs such as guarding, pulling sleds or carts and rescue work, including the Boxer, Rottweiler and Siberian Husky.

Working line vs show line: The split within one breed between dogs bred mainly for work or sport and dogs bred mainly for the show ring, which often differ in drive, build and energy.

X

X-ray: An imaging test that uses a small amount of radiation to show a dog's bones, chest and belly organs.

Xylitol: A sugar substitute in sugar-free gum, candy, baked goods and some peanut butters that is highly poisonous to dogs and a veterinary emergency.

Z

Zoomies: Sudden bursts of frantic running and circling, often after a bath or a long rest, which are normal and harmless in healthy dogs.