Tot of gin in crap punk dance (4)
I believe the answer is:
pogo
'punk dance' is the definition.
(dance associated with punk music)
'tot of gin in crap' is the wordplay.
'tot of' indicates taking the first letters (tot is a small amount, so only the first letter).
'in' is an insertion indicator.
'crap' becomes 'poo' (both can mean faeces).
The first letter of 'gin' is 'g'.
'g' inserted inside 'poo' is 'POGO'.
(Other definitions for pogo that I've seen before include "Punk movement" , "jump up and down" , "-- stick" , "gets jumped on by children" , "punk dancing" .)