Reason to limit booze (9)
I believe the answer is:
rationale
'reason' is the definition.
(thesaurus)
'limit booze' is the wordplay.
'limit' becomes 'ration' (rationing is a kind of limiting).
'booze' becomes 'ale' (I've seen this before).
'ration'+'ale'='RATIONALE'
'to' acts as a link.
(Other definitions for rationale that I've seen before include "Philosophy" , "Basis of logic" , "Logical reasons (for action)" , "solution in theory" , "The logical basis of some thing or action" .)