Expand entry to Eurovision to replace EU member's song (5)

I believe the answer is:

bulge

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'expand' is the definition.
(thesaurus)

I can't explain the rest of the clue.

(Other definitions for bulge that I've seen before include "Battle of the -----: last major German counter-offensive of WWII (1944)" , "surge?" , "Protrusion" , "Protuberance or outward swelling" , "Swelling - sudden increase" .)

I've seen this clue in The Times.

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