One sulky cat ran off irritably (14)

I believe the answer is:

cantankerously

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'irritably' is the definition.
Both the answer and definition are adverbs. Perhaps you can see an association between them that I can't see?

'one sulky cat ran off' is the wordplay.
'off' is an anagram indicator.
'one'+'sulky'+'cat'+'ran'='onesulkycatran'
'onesulkycatran' is an anagram of 'CANTANKEROUSLY'.

Can you help me to learn more?

(Another definition for cantankerously that I've seen is " In a temper".)

I've seen this clue in The Telegraph.

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