Island being ace, stick around (4)

I believe the answer is:

guam

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

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

(Other definitions for guam that I've seen before include "US unincorporated territory in the western Pacific" , "Island in the West Pacific" , "place in the Marianas" , "North Pacific island, base for the US navy and air force" , "US island east of the Philippines" .)

I've seen this clue in The Telegraph and The Sun.

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