Most horrific little woman given support (6)
I believe the answer is:
direst
'most horrific' is the definition.
('dire' can be a synonym of 'horrific')
'little woman given support' is the wordplay.
'little woman' becomes 'di' (short for Diane, Diana etc).
'given' means one lot of letters go next to another.
'support' becomes 'rest' (rest is a kind of support**).
'di'+'rest'='DIREST'
(Other definitions for direst that I've seen before include "far from ideal" , "Most horrific" .)