Named after the rabbit from Disney's Bambi, whose father told him "If you don't have anything nice to say, don't say anything at all." It is way of teaching of keeping derogatory comments to oneself in respect to those who aren't as able as you are to avoid conflict.
Male 1: Man, that a-hole is such a-
Male 2: Hey, remember Thumper's Law man.
Male 1: Fine, don't want any problems anyway.
Male 2: Hey, remember Thumper's Law man.
Male 1: Fine, don't want any problems anyway.
by Zaiaku September 15, 2016
A completely one sided fight that has one person all beaten up, while the other isn't even scratched.
by Zaiaku March 17, 2010