noun, plural arch·en·e·mies.
Examples from the Web for archenemy
He now reveals that Rich kept Israel alive through boycotts by supplying the country with oil, much of it from its archenemy Iran.
But he was not prepared for the skilful trap which his archenemy was baiting for him, and into which he was to promptly fall.The Night Riders|Ridgwell Cullum
Leithgow vouchsafed his archenemy no more than a look, but turned to the Hawk.The Passing of Ku Sui|Anthony Gilmore
And our archenemy dangling by the foot in mid-air, completely at our mercy!David and the Phoenix|Edward Ormondroyd