Like planetary paths (7)
I believe the answer is:
orbital
'like planetary paths' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for orbital that I've seen before include "(Of a road) going around a town" , "Circuitous" , "Going round - the M25?" , "Boil tar (anag)" , "Following a path around a heavenly body" .)