Corporation documents, puffed up (5)

I believe the answer is:

tumid

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'puffed up' is the definition.
(thesaurus)

'corporation documents' is the wordplay.
'corporation' becomes 'tum' ('corporation' is a humorous term for stomach fat).
'documents' becomes 'id' (I can't justify this - if you can you should believe this answer much more).
'tum'+'id'='TUMID'

Can you help me to learn more?

(Other definitions for tumid that I've seen before include "Bloated" , "Abnormally swollen" , "Bulging" .)

I've seen this clue in The Guardian.

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