A mental institution, insane asylum, etc.
My mom found my tinfoil hat last week and shipped me off to the nutbin.
by Alice V August 24, 2006
A crevasse or hole generally used for the storage or safe keeping of semen for future withdraw.
I had some extra jizz sitting around so I stashed it in her nut bin.
by puffsmckifin September 21, 2008