dog
n
1 bitch, canine, cur, hound, kuri or goorie (N.Z.) man's best friend, mongrel, mutt (slang) pooch (slang) pup, puppy, tyke
2 (informal) beast, blackguard, cur, heel (slang) knave (archaic) scoundrel, villain
3 dog-eat-dog cut-throat, ferocious, fierce, ruthless, vicious, with no holds barred
4 go to the dogs (informal) degenerate, deteriorate, go down the drain, go to pot, go to ruin
vb
5 haunt, hound, plague, pursue, shadow, tail (informal) track, trail, trouble