Change one name for a flower (7)
I believe the answer is:
anemone
'flower' is the definition.
(I know that anemone is a type of flower)
'change one name' is the wordplay.
'change' indicates an anagram.
'one'+'name'='onename'
'onename' anagrammed gives 'ANEMONE'.
'for a' is the link.
(Other definitions for anemone that I've seen before include "Plant; sea creature" , "The flower is no enema" , "Plant of the buttercup family - one name (anag)" , "Plant; marine creature" , "White woodland flower" .)