Boss in workplace having ten leaving (4)
I believe the answer is:
stud
'boss' is the definition.
(both can mean a metal decoration)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for stud that I've seen before include "Stallion; rivet" , "Specified arrangement" , "Stallion for breeding - fastener" , "Item designed to grip" , "who believes he can keep it up" .)