Ample nurse goes nearly crazy (8)
I believe the answer is:
generous
'ample' is the definition.
('generous' can be similar in meaning to 'ample')
'nurse goes nearly crazy' is the wordplay.
'nearly' means to remove the last letter.
'crazy' indicates an anagram.
'nurse'+'goes'='nursegoes'
'nursegoes' with its last letter taken away is 'nursegoe'.
'nursegoe' anagrammed gives 'GENEROUS'.
(Other definitions for generous that I've seen before include "More than adequate" , "Willing to give unselfishly" , "Munificent; liberal" , "Ample" , "Princely" .)