Opening for a token (4)
I believe the answer is:
slot
'opening for a token' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for slot that I've seen before include "This gaming machine operates by insertion of coin" , "Scheduled time -- aperture for coins" , "Small opening, for a coin say" , "Opening (for coins)" , "Lots (anag.)" .)