Nuts that are deprived of sexual intercourse therefore being "slacked" or "slacking".
Hey slacknuts, you aint got laid in months.
by Jerry Schlong June 27, 2006
when some is slacking off or doing a bad job..
haha look at george being a slack nut no more weed for him it make him.. i think hes gay.... yeah look how hes fondaling mr.shanks over there..
by kksdjaj aas f a September 01, 2006