Liquor found by abstainer hidden in tree trunk (6)
I believe the answer is:
bottle
'liquor' is the definition.
(thesaurus)
'abstainer hidden in tree trunk' is the wordplay.
'abstainer' becomes 'tt' (I've seen this in other clues).
'hidden in' indicates putting letters inside.
'tree trunk' becomes 'bole' (term for the trunk of a tree).
'tt' going inside 'bole' is 'BOTTLE'.
'found by' is the link.
(Other definitions for bottle that I've seen before include "confidence" , "Device used by beer drinkers" , "Heart" , "Glass or plastic vessel" , "Glass container - firmness of resolve" .)