Stud (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
boss
'stud' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for boss that I've seen before include "Domineer" , "One in charge; stud" , "27 [CHIEF]" , "Person managing" , "Informal employer or superior" .)