Quite a cocktail holding large drink (7)
I believe the answer is:
tequila
'drink' is the definition.
(tequila is a kind of drink)
'quite a cocktail holding large' is the wordplay.
'cocktail' is an anagram indicator.
'holding' means one lot of letters goes inside another.
'large' becomes 'l'.
'quite'+'a'='quitea'
'quitea' is an anagram of 'tequia'.
'tequia' placed around 'l' is 'TEQUILA'.
(Other definitions for tequila that I've seen before include "Mexican tipple" , "Mexican agave spirit" , "Mexican alcoholic drink" , "one in the slammer" , "Equal it! (anag)" .)