The seventh planet from the sun (6)
I believe the answer is:
uranus
'the seventh planet from the sun' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for uranus that I've seen before include "world" , "Planet that's the butt of much wordplay" , "Uses profane language" , "Planet - Greek god of the sky" , "Planet discovered in 1781 by Herschel" .)