Stop working, quickly, for a meal (9)
I believe the answer is:
breakfast
'meal' is the definition.
(I know that breakfast is a type of meal)
'stop working quickly' is the wordplay.
'stop working' becomes 'break' (I've seen this in another clue).
'quickly' becomes 'fast' (synonyms).
'break'+'fast'='BREAKFAST'
'for a' acts as a link.
(Other definitions for breakfast that I've seen before include "First meal at Tiffany's" , "One could be first on the table" , "Morning meal" , "Early meal" , "First meal of the day" .)