A crass Finn ruined company somewhere in America (3,9)
I believe the answer is:
san francisco
'somewhere in america' is the definition.
The answer and definition can be both locations as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'a crass finn ruined company' is the wordplay.
'ruined' is an anagram indicator.
'company' becomes 'co' (abbreviation).
'a'+'crass'+'finn'='acrassfinn'
'acrassfinn' anagrammed gives 'sanfrancis'.
'sanfrancis'+'co'='SAN FRANCISCO'
Can you help me to learn more?
(Other definitions for san francisco that I've seen before include "Nineteen hundred and six earthquake city" , "US west coast port" , "City in California" , "hilly city" , "Californian port" .)