Varmit

an awnry/ornery, pesky/pesty, grouchy, cantankerous, belligerent, tetchy, argumentative, crabby, unreasonable, or bad tempered HUMAN BEING OR CREATURE

Bugs Bunny asks Yosemite Sam for multiple items at dinner. Each time he is asked for something, Yosemite Sam loses his temper, and shouts out phrases like “Rackin’ Frackin’ Varmit Rabbit!!”

Cowboy common use: "Why you li'l VARMIT!!"