Fabled green lady - strange (9)
I believe the answer is:
legendary
'fabled' is the definition.
('legendary' can be a synonym of 'fabled')
'green lady strange' is the wordplay.
'strange' indicates anagramming the letters.
'green'+'lady'='greenlady'
'greenlady' with letters rearranged gives 'LEGENDARY'.
(Other definitions for legendary that I've seen before include "Fabled, celebrated" , "Mythical - very famous" , "Celebrated in fable" , "Romantic; fabulous" , "Fabled - green lady (anag)" .)