A less than engaging witticism (3)

I believe the answer is:

gag

'witticism' is the definition.
(gag is a kind of witticism)

'a less than engaging' is the wordplay.
'a less' indicates a hidden word (the clue less some of the letters in it).
'GAG' can be found hidden inside 'than engaging'.

(Other definitions for gag that I've seen before include "Muffle with slang joke" , "Muzzle in palindrome form" , "Censor" , "Muzzle or silence" , "Joke or muffler - a palindrome" .)

I've seen this clue in the Evening Standard.

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