Beers smug drunk sinks (9)
I believe the answer is:
submerges
'sinks' is the definition.
(submerging is a kind of sinking)
'beers smug drunk' is the wordplay.
'drunk' indicates anagramming the letters.
'beers'+'smug'='beerssmug'
'beerssmug' with letters rearranged gives 'SUBMERGES'.
(Other definitions for submerges that I've seen before include "Goes under, sinks" , "Dunks" .)