Gin drunk inside taverns for a spell (7)
I believe the answer is:
innings
'a spell' is the definition.
(thesaurus)
'gin drunk inside taverns' is the wordplay.
'drunk' is an anagram indicator.
'inside' means one lot of letters goes inside another.
'taverns' becomes 'inns' (I've seen this before).
'gin' is an anagram of 'ing'.
'ing' placed within 'inns' is 'INNINGS'.
'for' acts as a link.
(Other definitions for innings that I've seen before include "Chance to score" , "Period at the wicket" , "Batsman's spell at wicket" , "Batting score" , "(At cricket) a turn to bat" .)