Boss could give you endless work (4)
I believe the answer is:
stud
'boss' is the definition.
(both can mean a metal decoration)
'give you endless work' is the wordplay.
'give you' becomes 'stu' (I can't justify this - if you can you should believe this answer much more).
'endless' means to remove the last letter.
'work' becomes 'do work' (synonyms).
'do' with its final letter removed is 'd'.
'stu'+'d'='STUD'
'could' acts as a link.
Can you help me to learn more?
(Other definitions for stud that I've seen before include "Football boot's peg-like projection" , "Collar button or animal farm" , "Collar-fastener" , "upright" , "Football boot peg" .)