Left swallowed right - but not just now! (5)
I believe the answer is:
later
'not just now' is the definition.
Both the answer and definition are adverbs. Maybe you can see an association between them that I can't see?
'left swallowed right' is the wordplay.
'left' becomes 'L' (common abbreviation).
'swallowed' becomes 'ate' (swallow can mean to eat).
'right' becomes 'r' (common abbreviation).
'l'+'ate'+'r'='LATER'
'but' is the link.
Can you help me to learn more?
(Other definitions for later that I've seen before include "At a time in the future" , "More recent" , "In due course" , "Alert (anag.)" , "At a subsequent time" .)