Nuts: pick your meaning...

nuts |n?ts| informal
adjective [ predic. ]
mad: Going back to work today was nuts, but I think I managed

exclamation (often nuts to you (or him etc.))
an expression of contempt or derision

PHRASES
be nuts about (or Brit. on )like very much: I'm nuts about Blipfoto, and it helped me get through my surgical recovery

nut |n?t|
noun
1 a fruit consisting of a hard or tough shell around an edible kernel.
a small flat piece of metal or other material, typically square or hexagonal, with a threaded hole through it for screwing on to a bolt as a fastener.
? the part at the lower end of the bow of a violin or similar instrument, with a screw for adjusting the tension of the hair.
3 informal a crazy or eccentric person.
? [ with adj. or noun modifier ] a person who is excessively interested in or enthusiastic about a specified thing: a football nut.
4 informal a person's head.
5 (nuts) vulgar slang a man's testicles.
6 the fixed ridge on the neck of a stringed instrument over which the strings pass.
verb ( nuts, nutting, nutted )
1 [ with obj. ] Brit. informal butt (someone) with one's head.
2 [ no obj. ] (usu. as nounnutting) archaic gather nuts.

PHRASES
do one's nut Brit. informal become extremely angry or agitated.
nuts and bolts informal the basic practical details: the nuts and bolts of making a movie.
off one's nut informal out of one's mind; crazy.
a tough (or hard ) nut informal someone who is difficult to deal with; a formidable person.
a tough (or hard ) nut to crack informal a difficult problem or an opponent that is hard to beat.
use (or take ) a sledgehammer to crack a nut informal use disproportionately drastic measures to deal with a simple problem.