Jack Russell Terrier Glossary

Alphabetical list of terms related to Jack Russell Terriers and the JRTCA.

Affiliate - a local club whose purpose is to provide activities for, and communication between JR enthusiasts within a local geographic area. (more)
Agility - a trial event in which dogs traverse a maze of obstacles and compete for speed and accuracy. (more)
AKC (American Kennel Club) - the JRTCA is opposed to any form of all-breed registry or kennel recognition of the Jack Russell Terrier
BAER (Brainstem Auditory Evoked Response) - a test being used to eliminate or reduce the incidence of genetic expression of deafness from several breeds of dogs. (more)
Bilateral Deafness - inability to hear; i.e., completely deaf, both ears affected.
Brindle - a particular type of coat marking characterized by a pattern of black and brown; it is considered a registration fault.
Broken Coat - a coat the is very similar to a smooth coat but has trace hair on the head, face, legs or body. A broken coat needs minimal alterations to be ready for the show ring. They will generally only require a quick tidying up. A broken coat should not be soft - it should be harsh to provide protection from the elements. (more)
Bronze Medallion - a special honor given by the JRTCA to those Jack Russells and their owners who have earned three (or more) Natural Hunting Certificates Below Ground to different quarry. (more)
CERF (Canine Eye Registration Foundation) - a group of concerned purebred owner/breeders with a goal of eliminating heritable eye diseases in purebred dogs through registration, research, and education. (more)
Cerebellar Ataxia - degeneration of the cortex of the cerebellum leading to a staggering gait; it may or may not progress. (more)
COE (Code of Ethics) - The Breeders Code of Ethics outlines the ethical breeding practices expected of all JRTCA members. (more)
Conformation - a trial event in which the terrier is judged on the degree in which various angles and parts of the body agree or harmonize with each other (based on a breed standard). In addition to conformation and movement, the dog is judged on temperament; as in all things having to do with Jack Russells, the best working dog is being sought. (more)
Cross Entering - the act of entering your terrier in multiple conformation classes at a terrier trial (i.e., between the open and miscellaneous division)
Dam - the mother of a dog.
Dishing - fault action of a foreleg when a toe is thrown outward in a circular movement; it is considered a registration fault (more)
Go-to-Ground - a trial event designed to simulate and test a Jack Russell's ability to hunt and work underground. (more)
Hocks - the ankle joint.
Inbreeding - a breeding technique which pairs closely related animals, such as father-daughter, brother-sister, or cousins. Inbreeding favors genes of excellence as well as deleterious genes.
Incisors - the front teeth; in a dog there are a total of six upper and lower incisors.
JRTCA (Jack Russell Terrier Club of America) - the largest Jack Russell Terrier club and registry in the world; the National Breed Club and Registry for the Jack Russell Terrier in the United States. (more)
Legg Perthes - Aseptic necrosis of the head and neck of the femur, causes rear leg lameness; it is a disease of the hip joints of small breeds of dogs. (more)
Lens Luxation - dislocation of the lens from its normal site behind the cornea (partial or complete). (more)
Level Bite - the incisors meet cusp tip to cusp tip rather than have the uppers overlap the lowers (see scissor bite). This is an acceptable bite for a Jack Russell Terrier. (more)
Natural Hunting Certificate (NHC) - awarded for natural earthwork by the terrier and owner, judged by a sanctioned working judge, and is issued to only JRTCA registered or recorded dogs. (more)
Off-Lead - the act of running your terrier through an agility course without a leash. The terrier is controlled with hand and voice signals. (more)
On-Lead - the act of running your terrier through an agility course on a leash. After on-lead agility is mastered, the owner and terrier move to off-lead. (more)
Over Bite - a condition where the upper jaw is longer than the lower jaw. This is an unacceptable bite for a Jack Russell Terrier. (more)
Patella - the kneecap
Patellar Luxation - dislocation of the kneecap; can be inherited or acquired through trauma (more)
Plaiting - action when the terrier's feet cross over each other; it is considered a registration fault (more).
Prick Ears - a condition where the ears of a Jack Russell Terrier stick straight up; considered a registration fault.
Progressive Retinal Atrophy - degeneration of the retinal vision cells which progresses to blindness. (more)
PRTAA - the Parson Russell Terrier Association of America (formerly JRTAA); a breed club that pushed for AKC recognition of the Jack - now Parson - Russell Terrier against the wishes of the JRTCA; the PRTAA is considered a conflicting organization.
Refusal - when a terrier "commits" (places one foot on the obstacle) and fails to continue to perform on the obstacle in agility. (more)
Rough Coat - a coat that has excess trace hair on the head, face, legs or body. The hair is longer than on a smooth or broken coat. A rough coat requires more alterations than a broken coat to be ready for the show ring. A rough coat should not be soft or wooly - it should be harsh to provide protection from the elements. (more)
Sanctioned Trial - a terrier trial whose format is approved and sanctioned by the JRTCA. (more)
Scissor Bite (Incisor Overlap) - the upper incisors overlap the lower incisors. This is the recommended bite for a Jack Russell Terrier. (more)
Short or "High" Toes - this is a developmental condition where the outside toes, usually on one or both front feet, do not grow to normal length, giving the appearance of being a "short" or "high" toe that does not touch the ground when full the terrier is full grown. (more)
Sire - the father of a dog.
Span - the act of placing average size hands around the widest part behind the shoulders of the terrier; a small chest allows the terrier to follow his quarry down narrow earths (see picture). (more)
Smooth Coat - a coat that does not have trace hair on the head, face, legs or body. A smooth coat does not require any alterations to be ready for the show ring. The coat should not be sparse or soft - it should provide protection from the elements. (more)
State Representative - JRTCA members throughout the U.S. that provide information on the breed and the Club and act as liason for members in their respective areas. (more)
Stifle - the knee.
Stop - the point between a dog's eyes between the crown and the muzzle; the dip on the forehead.
terrier - The name terrier is derived from the French 'terre', meaning earth. The terrier's role is not to fight with its quarry, but to locate it underground and to bark at it continuously, either causing it to leave the earth or alternatively to indicate where in the earth the quarry is located - in order that it can be dug to.
Trace Hair - uncontrollable lengths of hair that does not lay close to the body. (more)
Trial Certificate - awarded to Jack Russells which achieve a 100 percent score in the Open Class of the Go-to-Ground Division at a JRTCA sanctioned trial. (more)
True Grit - the official magazine of the JRTCA; published bimonthly to all members. (more)
Umbilical Hernia - Outpouching of skin over belly button; may contain abdominal viscera, and regress spontaneously.
Under Bite - a condition where the lower jaw is longer than the upper jaw. This is an unacceptable bite for a Jack Russell Terrier. (more)
Unilateral Deafness - partial deafness; one ear affected. (more)
UKC (United Kennel Club) - an all breed registry of dogs.
Veterinary Certificate - designed specifically for the Jack Russell Terrier, this form must be completed and signed by a licensed veterinarian (within 30 days of application) stating that he has examined the terrier and found it to be free from inherited defects. Required for registration. (more)
Withers - the spot above the shoulders; the base of the neck.
Wobbler Syndrome - abnormality of the neck vertebrae causing rear leg ataxia which may progress to paralysis.
Wry - A wry mouth or wry bite occurs when one side of the jaw grows more than the other.