Former British possession in New York state (6)
I believe the answer is:
empire
This might be a double definition.
'former british possession' is the first definition.
'empire' can be an answer for 'possession' (thesaurus). I'm not sure about the 'former british' bit.
'new york state' is the second definition.
'empire' can be an answer for 'state' (Empire State is an example). I am not sure about the 'new york' bit.
'in' is the link.
Can you help me to learn more?
(Other definitions for empire that I've seen before include "Huge domain or group of companies" , "Several states ruled over by a single monarch" , "Group of countries under one authority" , "Former British-ruled countries" , "Group of states with a single monarch" .)