Island said approximately to have one tree? (6)

I believe the answer is:

cyprus

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'island' is the definition.
(Cyprus is an example)

I don't understand the remainder of the clue.

(Other definitions for cyprus that I've seen before include "Large East Mediterranean island" , "European island country" , "Partitioned Med. island" , "Divided Med. island" , "Mediterranean isle" .)

I've seen this clue in the Evening Standard.

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