Girl’s card game, lost at the end (7)
I believe the answer is:
bridget
'girl's' is the definition.
'card game lost at the end' is the wordplay.
'card game' becomes 'bridge' (bridge is a kind of card game).
'at the end' suggests the final letters.
The last letter of 'lost' is 't'.
'bridge'+'t'='BRIDGET'
(Other definitions for bridget that I've seen before include "Miss Jones the diarist" , "Girl" , "Saint" , "Saintly woman" .)