Starfish arms (4)
I believe the answer is:
rays
'starfish arms' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for rays that I've seen before include "Beams of sunlight" , "Sunbeams" , "Narrow beams of light" , "Straight lines extending from a point" , "Single lines of light" .)