Almost noble in New York (6)
'almost' is the definition.
'noble in new york' is the wordplay.
'noble' becomes 'earl' (earl is a kind of noble).
'in' indicates putting letters inside.
'new york' becomes 'ny'.
'earl' put into 'ny' is 'NEARLY'.
(Other definitions for nearly that I've seen before include "Almost, not quite", "pretty much", "More or less", "Not entirely", "approximately".)