A pondering that's funny (7)

I believe the answer is:

amusing

'that's funny' is the definition.
(amusing means funny or entertaining)

'a pondering' is the wordplay.
'pondering' becomes 'musing' (synonyms).
'a'+'musing'='AMUSING'

(Other definitions for amusing that I've seen before include "Entertaining in a mild way" , "comic" , "Pleasantly diverting" , "Causing a smile" , "Giving entertainment" .)

I've seen this clue in The Irish News.

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