Claims member tucked into alcoholic drinks (7)
I believe the answer is:
alleges
'claims' is the definition.
(I've seen this before)
'member tucked into alcoholic drinks' is the wordplay.
'member' becomes 'leg' (member can mean a limb).
'tucked into' means one lot of letters goes inside another.
'alcoholic drinks' becomes 'ales' (ale is a type of alcoholic drink).
'leg' going inside 'ales' is 'ALLEGES'.
(Other definitions for alleges that I've seen before include "Holds" , "Asserts without proof" , "Accuses without proof" , "Declares to be the case without proof" , "States without proof" .)