Fling nothing skywards - OK? (6)
I believe the answer is:
affair
'fling' is the definition.
(I've seen this before)
'nothing skywards ok?' is the wordplay.
'nothing' becomes 'fa'.
'skywards' says the letters should be written in reverse (in a down clue, letters go up).
'ok?' becomes 'fair' ().
'fa' reversed gives 'af'.
'af'+'fair'='AFFAIR'
(Other definitions for affair that I've seen before include "scandal" , "Vaguely specified concern" , "Concern,matter" , "A matter; amorous episode" , "A function or a romance" .)