Irving city?
I believe the answer is:
berlin
This might be a double definition.
'irving' is the first definition.
Both the answer and definition are singular nouns.
Perhaps there's a link between them I don't understand?
'city?' is the second definition.
(Berlin is an example)
Can you help me to learn more?
(Other definitions for berlin that I've seen before include "German city" , "Irving . . . . . . , great American song-writer" , "Composer < in carriage < in European capital" , "Composer of White Christmas" , "A once-divided city" .)