Former playgirl's heart goes to single bishop first (6)
I believe the answer is:
bygone
'former' is the definition.
(thesaurus)
'playgirl's heart goes to single bishop first' is the wordplay.
'heart' indicates the central letters.
'goes to' is a charade indicator (letters next to each other).
'single' becomes 'one' (I've seen this before).
'bishop' becomes 'b' (abbreviation used in chess).
'first' means one lot of letters go next to another.
The middle of 'playgirl' is 'yg'.
'yg' put next to 'one' is 'ygone'.
'ygone' after 'b' is 'BYGONE'.
(Other definitions for bygone that I've seen before include "Olden (days)" , "Times past, poetically" , "Gone by (anag.)" , "Of departed days" , "Former - well in the past" .)