Non-drinker swallowing an alcoholic drink in fit of temper (7)
I believe the answer is:
tantrum
'fit of temper' is the definition.
'non-drinker swallowing an alcoholic drink' is the wordplay.
'non drinker' becomes 'tt' (Teetotaller abbreviation).
'swallowing' means one lot of letters goes inside another.
'alcoholic drink' becomes 'rum' (I've seen this before).
'tt' going around 'an' is 'tant'.
'tant'+'rum'='TANTRUM'
'in' is the link.
(Other definitions for tantrum that I've seen before include "Paddy" , "petulant outburst" , "Fit of ill-temper" , "fit of bad temper" , "Wobbly" .)