Popular name for hotel (3)
I believe the answer is:
inn
'for hotel' is the definition.
(inn is a kind of hotel)
'popular name' is the wordplay.
'popular' becomes 'in' ('in' can mean trendy).
'name' becomes 'n' (common abbreviation e.g. on forms).
'in'+'n'='INN'
(Other definitions for inn that I've seen before include "Old hostelry for travellers" , "It provides rest for the traveller" , "Country pub, often with accommodation" , "watering-hole" , "Pub providing food and accommodation" .)