Stout, excellent pressure (5)

I believe the answer is:

plump

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'stout' is the definition.
(I've seen this before)

'excellent pressure' is the wordplay.
'excellent' becomes 'plum' (I can't explain this - if you can you should give a lot more credence to this answer).
'pressure' becomes 'p' (abbreviation).
'plum'+'p'='PLUMP'

Can you help me to learn more?

(Other definitions for plump that I've seen before include "Having a full rounded shape" , "Opt - round" , "Well-rounded" , "Fat - set down unceremoniously" , "Fat - fatten" .)

I've seen this clue in The Mirror.

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