Absurd request -- go bananas (9)
I believe the answer is:
grotesque
'absurd' is the definition.
(thesaurus)
'request go bananas' is the wordplay.
'bananas' is an anagram indicator (bananas can informally mean crazy).
'request'+'go'='requestgo'
'requestgo' anagrammed gives 'GROTESQUE'.
(Other definitions for grotesque that I've seen before include "Bizarre; monstrous" , "Horribly distorted" , "Fantastically hideous" , "Bizarre and disfigured - preposterous" , "Freakish" .)