Disbeliever in gods (7)
I believe the answer is:
atheist
'disbeliever in gods' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for atheist that I've seen before include "Someone who denies the existence fo God" , "One who has no belief in a god" , "One not believing in gods" , "Disbeliever in deities" , "One who believes there is no god" .)