A number enjoy something (5)
I believe the answer is:
digit
'a number' is the definition.
(digit is a kind of number)
'enjoy something' is the wordplay.
'enjoy' becomes 'dig' (to dig can mean to appreciate or 'get').
'something' becomes 'it' (both can refer to an object).
'dig'+'it'='DIGIT'
(Other definitions for digit that I've seen before include "Single number" , "A character" , "Single figure - finger" , "finger, perhaps" , "One in ten, say" .)