Galaxy (5,3)
I believe the answer is:
milky way
'galaxy' is the definition.
(I know that Milky Way is a type of galaxy)
This is the entire clue.
(Other definitions for milky way that I've seen before include "Lots of stars" , "Star-studded band" , "Galaxy containing our solar system" , "Millions of stars in a band of light across the night sky" , "Galaxy, broad faintly luminous band of stars" .)