Old heartless swine in New York, prying (5)
I believe the answer is:
nosey
'prying' is the definition.
(synonyms)
'old heartless swine in new york' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'heartless' suggests removing the centre.
'in' is an insertion indicator.
'new york' becomes 'ny'.
'swine' with its centre removed is 'se'.
'o'+'se'='ose'
'ose' placed within 'ny' is 'NOSEY'.
(Other definitions for nosey that I've seen before include "Offensively curious or inquisitive" , "Impertinent" , "Prying" , "Curious in nasal way" , "Showing too much interest in other people's affairs" .)