Starfish formed by a biochemical compound (8)
I believe the answer is:
asteroid
'starfish' is the definition.
(I've seen this in another clue)
'a biochemical compound' is the wordplay.
I cannot really understand how this works, but
'a' is present in the answer.
'compound' could be 'steroid' (steroid is a kind of compound) and 'steroid' is present in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'formed by' is the link.
Can you help me to learn more?
(Other definitions for asteroid that I've seen before include "Small celestial body composed of rock and metal" , "Lump of rock orbiting the sun" , "Piece of rock that moves around the heavens" , "looking like a star?" , "Small rocky object orbiting the sun - store aid (anag)" .)