Covering the female with a what's-it (9)
I believe the answer is:
sheathing
'covering' is the definition.
(sheathing is a kind of covering)
'female with a what's-it' is the wordplay.
'female' becomes 'she' ('she' refers to a woman).
'with' says to put letters next to each other.
'what's it' becomes 'thing'.
'she'+'a'+'thing'='SHEATHING'
'the' is the link.
(Other definitions for sheathing that I've seen before include "putting it in a case" , "protective covering" .)