Belladonna lily (9)
I believe the answer is:
amaryllis
'belladonna lily' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for amaryllis that I've seen before include "Plant with showy flowers - I rally Sam (anag)" , "Trumpet-flowered bulb" , "Bulb with showy flowers" , "Lily-like plant" , "belladonna lily brought this about" .)