Genre associated with science fiction (7)
I believe the answer is:
fantasy
'genre associated with science fiction' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for fantasy that I've seen before include "Imagination unrestricted by reality" , "Fay tans badly and forms a mental image" , "Unreal idea" , "Whimsical, imaginative, notion" , "The imagining of what is impossible" .)