The New Dictionary of Cultural Literacy, Third Edition. 2002.
alloy
(AL-oy, uh-LOY) A material made of two or more metals, or of a metal and another material. For example, brass is an alloy of copper and zinc; steel is an alloy of iron and carbon. Alloys often have unexpected characteristics. In the examples given above, brass is stronger than either copper or zinc, and steel is stronger than either iron or carbon.