Seen in royal racecourse, topless Northerner (4)

I believe the answer is:

scot

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'northerner' is the definition.
(someone from Scotland)

I cannot understand how the remainder of the clue works.

(Other definitions for scot that I've seen before include "Someone from north of the border?" , "levy, once" , "Highlander perhaps" , "Eg, a Glaswegian" , "British northerner" .)

I've seen this clue in The Everyman puzzle in The Observer.

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