Bull, boar or buck (4)
I believe the answer is:
male
I believe this clue is a double definition.
'bull' is the first definition.
(thesaurus)
'boar or buck' is the second definition.
(I've seen this in another clue)
(Other definitions for male that I've seen before include "Maldives capital; masculine" , "Lame sort of fellow" , "A gender" , "man?" , "As are drakes, bulls etc." .)