Stud manager (4)
I believe the answer is:
boss
I believe this is a double definition.
'stud' is the first definition.
(synonyms)
'manager' is the second definition.
(I've seen this in another clue)
(Other definitions for boss that I've seen before include "Team manager" , "Behave overbearingly" , "27 [CHIEF]" , "Governor" , "One in charge; stud" .)