Get drunk fast (5)
I believe the answer is:
tight
'fast' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for tight that I've seen before include "Close-fitting; cramped; mean" , "Drunk; giving little room" , "lack of money" , "corked?" , "reluctant to buy a round?" .)