Singer needing most of seat? (4)
I believe the answer is:
diva
'singer' is the definition.
(diva can mean a female opera singer)
'most of seat?' is the wordplay.
'most of' means to remove the last letter.
'seat?' becomes 'divan' (divan is a kind of seat).
'divan' with its final letter taken away is 'DIVA'.
'needing' is the link.
(Other definitions for diva that I've seen before include "demanding woman" , "Avid like opera singer" , "Operatic female singer" , "Great performer" , "Distinguished female singer" .)