Viennese person took turn on the continent (4)

I believe the answer is:

asia

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'continent' is the definition.
(Asia is an example)

I cannot understand how the rest of the clue works.

(Other definitions for asia that I've seen before include "populous region" , "The Orient" , "Earth's largest continent" , "Put out" , "A is A (anag)" .)

I've seen this clue in The Irish Times.

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