Flipped over say, darkish bug (5)
I believe the answer is:
midge
'bug' is the definition.
'flipped over say darkish' is the wordplay.
'flipped over' is a reversal indicator.
'say' becomes 'eg' (both can mean for example).
'darkish' becomes 'dim' (I've seen this in another clue).
'eg'+'dim'='egdim'
'egdim' in reverse letter order is 'MIDGE'.
(Other definitions for midge that I've seen before include "Small, gnat-like fly" , "Tiny swarming fly" , "A small biting gnat-like insect" , "Dipterous insect, in swarms by water" , "Minute mosquito-like fly" .)