Vocalist forced to resign (6)
I believe the answer is:
singer
'vocalist' is the definition.
(synonyms)
'forced to resign' is the wordplay.
'forced' indicates an anagram.
'resign' is an anagram of 'SINGER'.
(Other definitions for singer that I've seen before include "Bass, say" , "choirboy?" , "Eg, tenor" , "Vocalist" , "Song performer" .)