Foreign language - could be French (6)

I believe the answer is:

polish

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

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

(Other definitions for polish that I've seen before include "'Buff, burnish (6)'" , "Buff - from Poland" , "Shine up the nationality" , "European language - refinement" , "Shine up in Warsaw" .)

I've seen this clue in The Guardian and The Globe and Mail.

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