An insult or insults that are sufficiently offensive to the insulted person that he/she becomes angry enough to start throwing punches.
Person 1: Too bad your mama didn't drown you when you were born, you worthless nigger/kike/camel jockey/bitch/cracker/gook/insert chosen offensive word(s) here!
Person 2: I'm gonna beat your ass! Them's fightin' words!
Person 2: I'm gonna beat your ass! Them's fightin' words!
by Evil Tim June 18, 2004
by The Return of Light Joker October 04, 2007
An old-time expression interjected after one is on the receiving end of a harsh criticism. A fight will usually occur as a result.
Northerner: You're a dumbass from the south, and so is your slave beating mother.
Southerner: (draws gun) Them's fightin' words!
Southerner: (draws gun) Them's fightin' words!
by dilary huff August 17, 2007