Romantic version of Lady Green
I believe the answer is:
legendary
'romantic' is the definition.
(thesaurus)
'version of lady green' is the wordplay.
'version of' indicates anagramming the letters.
'lady'+'green'='ladygreen'
'ladygreen' with letters rearranged gives 'LEGENDARY'.
(Other definitions for legendary that I've seen before include "Well-known" , "Fabled - green lady (anag)" , "notorious" , "Mythical - very famous" , "Relating to old or mythological tales" .)