Nearly all nuts and fruit (6)
I believe the answer is:
banana
'fruit' is the definition.
(banana is a kind of fruit)
'nearly all nuts' is the wordplay.
'nearly all' means to remove the last letter.
'nuts' becomes 'bananas' (as in crazy).
'bananas' with its final letter taken off is 'BANANA'.
'and' acts as a link.
(Other definitions for banana that I've seen before include "Elongated edible fruit" , "Sub-tropical fruit" , "Yellow-skinned fruit" , "Fruit led by prohibition" , "Small politically unstable country dominated by foreign companies" .)