Credible, therefore, about waffle (7)

I believe the answer is:

blether

'waffle' is the definition.
(thesaurus)

'credible therefore about' is the wordplay.
'about' indicates a hidden word (the clue goes around or about the answer).
'BLETHER' is hidden within 'credible therefore'.

(Other definitions for blether that I've seen before include "Yak" , "Idle talk" , "gossip" , "gas" .)

I've seen this clue in The Daily Express.

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