One unspecified area west of New York (3)
I believe the answer is:
any
'one unspecified' is the definition.
(any example of something)
'area west of new york' is the wordplay.
'area' becomes 'a' (maths abbreviation).
'west of' says to put letters next to each other.
'new york' becomes 'ny'.
'a'+'ny'='ANY'
(Other definitions for any that I've seen before include "One or some, whichever you choose" , "A lot < ? Not a lot < -- some" , "Some; none in particular" , "One (unspecified)" , "At all; in some degree" .)