Put a cross in the middle (7)

I believe the answer is:

centred

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

I don't understand how the rest of the clue works.

(Other definitions for centred that I've seen before include "Moved to the middle" , "Placed in the middle" , "Positioned centrally" , "half way across?" .)

I've seen this clue in the Evening Standard.

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