For the drunk, deprived of a bottle opener, it's just a game (5)
I believe the answer is:
lotto
'game' is the definition.
(the UK National Lottery)
'for the drunk deprived of a bottle opener it's just a' is the wordplay.
I cannot really see how this works, but
'for' could be 'to' (eg both can mean 'in the opinion of') and 'to' is present in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
'of' could be 'o' and 'o' is present in the answer.
A single letter 'l' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for lotto that I've seen before include "Game in which numbers are drawn" , "Housey-housey, bingo" , "Bingo - Venetian painter" , "Game of chance similar to bingo" , "Children's game; lottery" .)