“Antonomasia: [Stress: ‘an-to-no-May-zy-a’]. 1. In rhetoric, the use of an epithet to acknowledge a quality in one person or place by using the name of another person or place already known for that quality: Henry is the local Casanova; Cambridge is England’s Silicon Valley. 2. The use of an epithet instead of the name of a person or thing: the Swan of Avon William Shakespeare.”
Excerpted from: McArthur, Tom. The Oxford Concise Companion to the English Language. New York: Oxford University Press, 2005.