Ruling class (5)

I believe the answer is:

order

This clue is a double definition.

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

'class' is the second definition.
(I've seen this in another clue)

(Other definitions for order that I've seen before include "Group living under a religious rule" , "demanding firm discipline" , "plan to reorganise Europe with 1a [NEW]" , "Directive for harmony" , "kind > direction" .)

I've seen this clue in The Sun and The Times.

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