Boss backing out of room (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 "Large-headed piece of metal - horse-breeding establishment" , "Bejewel" , "Large headed nail" , "Type of poker, a collar and a farm" , "Style of poker" .)