Strikes as copper's restraining two females (5)
I believe the answer is:
cuffs
'strikes' is the definition.
(I've seen this before)
'copper's restraining two females' is the wordplay.
'copper's' becomes 'cus' (chemical symbol).
'restraining' indicates putting letters inside.
'two females' becomes 'ff'.
'cus' enclosing 'ff' is 'CUFFS'.
'as' is the link.
(Other definitions for cuffs that I've seen before include "bracelets" , "Clips around the ear" , "Strikes with an open hand" , "Hits" , "boxes" .)