Piece of land apparently not untenanted (5)

I believe the answer is:

islet

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'piece of land' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for islet that I've seen before include "Detached territory" , "Small piece of land surrounded by water" , "Minor key" , "detached territories?" , "Stile (anag)" .)

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

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