Boss takes actor round colliery (8)
I believe the answer is:
domineer
'boss' is the definition.
(I've seen this before)
'actor round colliery' is the wordplay.
'actor' becomes 'doer' (synonyms).
'round' means one lot of letters goes inside another.
'colliery' becomes 'mine' (a colliery is a coal mine).
'doer' enclosing 'mine' is 'DOMINEER'.
'takes' acts as a link.
(Other definitions for domineer that I've seen before include "Ore mined badly could tend to overbear" , "Exercise power over in an autocratic manner" , "Deem iron to be changed to overbear" , "Behave imperiously" , "Dine more and be overbearing" .)