To smack, slap or impede in any way the act of a sexual groping, especially from an annoying boyfriend who just wants to grab a titty or a cheek for grabbin's sake (because that's his ass to grab). This definition is reversible for male-to-female, except most men will opt out of the knock away and allow the grope in almost any instance.

A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.