Stupidly I bait red in bitter attack (8)
I believe the answer is:
diatribe
'bitter attack' is the definition.
(I've seen this before)
'stupidly i bait red' is the wordplay.
'stupidly' is an anagram indicator (a stupid ordering of the letters).
'i'+'bait'+'red'='ibaitred'
'ibaitred' anagrammed gives 'DIATRIBE'.
'in' acts as a link.
(Other definitions for diatribe that I've seen before include "Philippic" , "critical speech" , "Strong words" , "Bitter words" , "Stream of invective" .)