Star in Lyra (4)
I believe the answer is:
vega
'star in lyra' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for vega that I've seen before include "Bright star of constellation Lyra" , "Brightest star of constellation Lyra" , "Fifth brightest star" , "heavenly body" , "First magnitude star" .)