Bill Lock - player (7)
I believe the answer is:
actress
'player' is the definition.
(actress is a kind of player)
'bill lock' is the wordplay.
'bill' becomes 'act' (I've seen this in other clues).
'lock' becomes 'ress' (I've seen this in another clue).
'act'+'ress'='ACTRESS'
(Other definitions for actress that I've seen before include "eg Emma Thompson" , "Female performer" , "One playing" , "dame on stage?" , "Theatrical female" .)