US city cross with company importing silver (7)
I believe the answer is:
chicago
'us city' is the definition.
(Chicago is a US city)
'cross with company importing silver' is the wordplay.
'cross with' becomes 'chi' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'company' becomes 'co' (abbreviation).
'importing' means one lot of letters goes inside another.
'silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'co' enclosing 'ag' is 'cago'.
'chi'+'cago'='CHICAGO'
Can you help me to learn more?
(Other definitions for chicago that I've seen before include "Al Capone's city" , "US city, original home of the skyscraper" , "Port on Lake Michigan" , "3 city in the US" , "America's Windy City" .)