Person somewhat left out (5)

I believe the answer is:

party

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'person' is the definition.
(eg an individual in a court case)

I cannot understand how the rest of the clue works.

(Other definitions for party that I've seen before include "Bash" , "Political organization" , "Crew" , "festive" , "Shooting weapon" .)

I've seen this clue in The Independent.

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