Diary penned by Pooter, e.g. is terrific (8)

I believe the answer is:

'diary' is the definition.
(thesaurus)

'penned by pooter e g is terrific' is the wordplay.
'penned by' indicates a hidden word.
'REGISTER' is hidden within 'pooter e g is terrific'.

(Other definitions for register that I've seen before include "Official list or record" , "Greet sir (anag.)" , "(Put one's name down on) list" , "To express" , "Make an impression: sign on" .)

I've seen this clue in The Times.

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