Mike in market produces pong (5)
I believe the answer is:
smell
'pong' is the definition.
Both the definition and answer are singular nouns.
Maybe you can see an association between them that I can't see?
'mike in market' is the wordplay.
'mike' becomes 'M' (phonetic alphabet: alpha, bravo, charlie etc.).
'in' means one lot of letters goes inside another.
'market' becomes 'sell' (I've seen this before).
'm' put within 'sell' is 'SMELL'.
'produces' acts as a link.
Can you help me to learn more?
(Other definitions for smell that I've seen before include "Nasal sense" , "Scent" , "Aroma" , "stink" , "Unpleasant odour" .)