Diatribe's answer resounded in tone (8)
I believe the answer is:
harangue
'diatribe's' is the definition.
(I've seen this before)
'answer resounded in tone' is the wordplay.
'answer' becomes 'a' (abbreviation eg in Q and A).
'resounded' becomes 'rang' ('ring' can be a synonym of 'resound').
'in' indicates putting letters inside.
'tone' becomes 'hue' (both can mean a colour).
'a'+'rang'='arang'
'arang' placed into 'hue' is 'HARANGUE'.
(Other definitions for harangue that I've seen before include "Exhortation" , "A lengthy speech or scolding" , "Tirade, diatribe" , "Speak loudly (at)" , "A lengthy earnest speech" .)