Break up civil riot expressing considerable bitterness (9)

I believe the answer is:

vitriolic

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'expressing considerable bitterness' is the definition.
I can't tell whether this defines the answer.

'break up civil riot' is the wordplay.
'break up' indicates an anagram.
'civil'+'riot'='civilriot'
'civilriot' with letters rearranged gives 'VITRIOLIC'.

Can you help me to learn more?

(Other definitions for vitriolic that I've seen before include "Cruelly savage (criticism)" , "Acrimonious" , "Highly corrosive" , "biting" , "Scathing" .)

I've seen this clue in The Telegraph.

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