Below are some of the commonly used "Dog Show" abbreviations with definition.

WD

This stands for Winner's Dog which refers to the "Male" that beats all the other males from the other classes for the points that day.

WB

This stands for Winner's Bitch which refers to the "Female" that beat all the other females from the other classes for the points that day.

RWD

This stands for Reserve Winner's Dog which refers to the "Male" that is declared the "runner-up" to Winner's Dog.  If Winner's Dog is deemed ineligible for the points they will be awarded to the male that wins RWD.

RWB

This stands for Reserve Winner's Bitch which refers to the "Female" that is declared the "runner-up" to Winner's Bitch.  If Winner's Bitch is ineligible for the pointe they will be awards to the female that wins RWB.

BOW

This means Best Of Winner's which refers to the best between Winner's Dog and Winner's Bitch.

BOS

This means Best Of Opposite Sex which refers to the dog that is the best of the opposite sex to Best of Breed.  If Best of Breed is a male then Best of Opposite sex is a female.  BOS can also be awarded to Winner's Dog or Winner's Bitch.

BOB

This means Best Of Breed which refers to the best dog of that breed that day.  This placement could be either male or female and it could also be either Winner's Dog or Winner's Bitch, whichever dog the judge chooses at it best that day.  The winner of BOB will also compete in their Group.

G1, G2, G3, & G4

These refer to placements a dog was awarded within their group.  If a dog wins a G1 then they will compete for Best In Show.

BIS

This stands for Best In Show, which refers to the dog that was the best in the whole show that day.

RBIS

This means Reserve Best In Show.  Some Kennel Organizations like the UKC will award this placement to the dog that the judge feel was "runner-up" to Best In Show.

BP

This stands for Best Puppy, which refers to the puppy that was the Best of Breed that day.  The Best Puppy will then compete in their groups for placements.

PG1, PG2, PG3, & PG4

This stands for the placements within the Puppy Groups.  The Puppy that wins the Puppy Group 1 will then compete for Best Puppy In Show.

BPIS

This stands for Best Puppy In Show, which refers to the Puppy that was the Best Puppy In Show that day.

BBBE

This stands for Best Bred By Exhibitor, which refers to the dog that was the best from the Bred-By Exhibitor class.  (Only the breeder can show in the Bred-By Class)

BBEG1, BBEG2, BBEG3, & BBEG4

This stands for the placements within the Bred-By Exhibitor groups.  The dog that wins this group will compete for Best Bred-By In Show.

BBES

This stands for Best Bred-By Exhibitor In Show, which refers to the dog that was the Bred Bred-By In Show that day.

BISS

This stands for Best In Specialty Show, which refers to the dog that wins BOB at a specialty show (a specialty show is a show where there is only 1 breed present)

BOSS

This stands for Best of Opposite Sex In Specialty show, which refers to the dog that is the brest of the opposite sex.

CH

This stands for Champion, it will go in front of the dog's registered name after they complete the required points for a champion title.

AKC

This stands for the American Kennel Club

UKC

This stands for the United Kennel Club

Gr CH.

This stand for Grand Champion, it will go in front of the dog's registered name after they complete the requirements for this grand champion title.