City can produce lingo (5)
I believe the answer is:
latin
'lingo' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'city can' is the wordplay.
'city' becomes 'LA' (Los Angeles).
'can' becomes 'tin' (both are metal containers).
'la'+'tin'='LATIN'
'produce' is the link.
Can you help me to learn more?
(Other definitions for latin that I've seen before include "a quarter of Parisians" , "Language of old Romans" , "Shakespeare's was small, according to Jonson" , "Hispanic, for example" , "Language of Cicero" .)