Part of deck sees action (4)

I believe the answer is:

suit

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'action' is the definition.
(synonyms)

I cannot understand how the rest of the clue works.

(Other definitions for suit that I've seen before include "Part of pack (of cards)" , "Formal attire" , "Formal wear (for court action?)" , "See 10" , "Matching jacket and trousers" .)

I've seen this clue in The Independent.

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