Marked and forced right out (7)

I believe the answer is:

stained

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

I cannot understand how the rest of the clue works.

(Other definitions for stained that I've seen before include "Marked, discoloured" , "Church feature - side sold was wanting (anag)" , "Like many church windows" , "___ glass" , "Soiled" .)

I've seen this clue in The Guardian.

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