Male or female? Not entirely (3)
I believe the answer is:
lad
'male' is the definition.
(lad is a kind of male)
'female? not entirely' is the wordplay.
'female?' becomes 'lady' (lady is a kind of female).
'not entirely' means to remove the last letter.
'lady' with its final letter removed is 'LAD'.
'or' acts as a link.
(Other definitions for lad that I've seen before include "A young chap into ballads" , "Young fellow" , "Boy, familiar" , "Boy, young man" , "Scottish lover" .)