Popular new place for an overnight stay (3)
I believe the answer is:
inn
'place for an overnight stay' is the definition.
(an inn is a place to say)
'popular new' is the wordplay.
'popular' becomes 'in' ('in' can mean trendy).
'new' becomes 'n' (abbreviation as in New Testament NT).
'in'+'n'='INN'
(Other definitions for inn that I've seen before include "watering-hole" , "Old hostelry for travellers" , "Pub with lodging" , "eg the Tabard" , "Hotel with lodging for travellers" .)