Parody it as returns go up (8)
I believe the answer is:
satirise
'parody' is the definition.
(I've seen this before)
'it as returns go up' is the wordplay.
'returns' says the letters should be written in reverse.
'go up' becomes 'rise' (rising is a kind of going up).
'it'+'as'='itas'
'itas' reversed gives 'sati'.
'sati'+'rise'='SATIRISE'
(Other definitions for satirise that I've seen before include "parody" , "Ridicule someone on stage" , "Send up" , "Use humour to insult or expose stupidity" , "Ridicule with irony" .)