About to wake up and drink (7)
I believe the answer is:
carouse
'drink' is the definition.
(thesaurus)
'about to wake up' is the wordplay.
'about' becomes 'ca' (abbreviation for circa).
'to wake up' becomes 'rouse' (rouse can mean to wake up).
'ca'+'rouse'='CAROUSE'
'and' is the link.
(Other definitions for carouse that I've seen before include "Engage in boisterous, drunken merry-making" , "booze" , "Celebrate noisily" , "Drink and make merry" , "Drink a lot" .)