Mexican liquor (7)
I believe the answer is:
tequila
'mexican liquor' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for tequila that I've seen before include "Distilled agave drink" , "Mexican tipple" , "Mexican alcoholic drink" , "Quit ale for Mexican spirit" , "Mexican liquor made from agave" .)