Humorously critical of racialist, perhaps (9)
I believe the answer is:
satirical
'humorously critical' is the definition.
(I've seen this before)
'racialist perhaps' is the wordplay.
'perhaps' indicates an anagram.
'racialist' is an anagram of 'SATIRICAL'.
'of' is the link.
(Other definitions for satirical that I've seen before include "Ironic - sarcastic" , "Ridiculing" , "Exposing human folly to ridicule" , "Poking fun at" , "Humorously critical" .)