Teetotaller entering place for stiff drink (6)
I believe the answer is:
bitter
'drink' is the definition.
(bitter is a kind of drink)
'teetotaller entering place for stiff' is the wordplay.
'teetotaller' becomes 'tt' (abbreviation).
'entering' indicates putting letters inside.
'place for stiff' becomes 'bier' (a bier is a stand for a dead body or stiff).
'tt' put within 'bier' is 'BITTER'.
(Other definitions for bitter that I've seen before include "Unpalatable; a beer" , "drink" , "Acrimonious; beer" , "Acerbic" , "Beer; not sweet" .)