Flower beheaded more quickly (5)
I believe the answer is:
aster
'flower' is the definition.
(type of flower)
'beheaded more quickly' is the wordplay.
'beheaded' means to remove the first letter (the head of the word is removed).
'more quickly' becomes 'faster' (synonyms).
'faster' with its first letter taken away is 'ASTER'.
(Other definitions for aster that I've seen before include "It grows" , "Daisy-like garden flower" , "Kind of daisy" , "Showy garden flower" , "Flower of the daisy family - rates (anag)" .)