Fish meal oddly rejected: apart from the stigma, it also has style (6)
I believe the answer is:
carpel
'apart from the stigma it also has style' is the definition.
(female reproductive organ of flower)
'fish meal oddly rejected' is the wordplay.
'fish' becomes 'carp' (carp is a kind of fish**).
'oddly rejected' means one should take alternating letters.
The alternating letters of 'meal' are 'el'.
'carp'+'el'='CARPEL'
(Other definitions for carpel that I've seen before include "Part of a flower" , "organ" , "bit of a flower" .)