Self-controlled expanse of land (9)

I believe the answer is:

continent

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'land' is the definition.
(I know that continent is a type of land mass)

I don't understand the remainder of the clue.

(Other definitions for continent that I've seen before include "Maybe more than one country" , "Sober" , "Monk vows" , "Europe, say" , "huge area of land" .)

I've seen this clue in The Daily Express.

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