Case one of four (4)

I believe the answer is:

suit

I believe this is a double definition.

'case' is the first definition.
('suit' can be a synonym of 'case')

'one of four' is the second definition.
(a deck of cards has 4 suits)

(Other definitions for suit that I've seen before include "Complement" , "Do as you please!" , "Befit" , "Matching jacket and trousers" , "diamonds, perhaps" .)

I've seen this clue in The Guardian.

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