Not eating quickly (4)
I believe the answer is:
fast
'quickly' is the definition.
(synonyms)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for fast that I've seen before include "Renounce food; quick" , "sort of convenience food" , "Brisk" , "Quick - stop eating" , "fare-dodging" .)