Nothing on after light satire (7)
I believe the answer is:
lampoon
'satire' is the definition.
(I've seen this before)
'nothing on after light' is the wordplay.
'nothing' becomes 'O' (O resembles 0).
'after' says to put letters next to each other.
'light' becomes 'lamp' (lamp is a kind of light).
'o'+'on'='oon'
'oon' after 'lamp' is 'LAMPOON'.
(Other definitions for lampoon that I've seen before include "Piece of writing that ridicules someone" , "Make fun of" , "Satirical work" , "Parody" , "Pool man (anag)" .)