A shiner, it seems, will make you scowl (6)

I believe the answer is:

glower

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

I can't explain the remainder of the clue.

(Other definitions for glower that I've seen before include "Angry stare" , "Look hard and angrily" , "Angry and sullen look" , "shiner?" , "Look black" .)

I've seen this clue in the Evening Standard.

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