Cluster, as of grass (4)
I believe the answer is:
tuft
'cluster as of grass' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tuft that I've seen before include "Bunch of threads or grass" , "Small bunched cluster" , "Bunch of hairs" , "Small bunch of grass, hair etc" , "Dog's lead" .)