'below the belt' definitions:

Definition of 'below the belt'

From: WordNet
adverb
In an unfair manner; "they dealt with him unfairly"; "their accusations hit below the belt" [syn: unfairly, below the belt] [ant: clean, fair, fairly]
adjective
Disregarding the rules (from the notion of an illegal low blow in boxing); "her accusations were below the belt"