Lily (4)

I believe the answer is:
arum
'lily' is the definition.
(a type of lily)
This is the entire clue.
(Other definitions for arum that I've seen before include "Plant with small flowers and arrow-shaped leaves - kind of lily" , "Eg, cuckoo pint" , "Cuckoo pint is one such" , "A spirit for a lily" , "Plant like cuckoo pint" .)