1. A mixture of a metal with smaller quantities of other metals, or even nonmetals, to make it harder, to survive high temperatures, or to improve it in other ways.

Alloy wheels on vehicles use strong, lightweight alloys, that are based on aluminum.

2. Any of various materials having metallic properties and composed of two or more closely mixed chemical elements, of which at least one is a metal; for example, brass is an alloy of copper and zinc.

Alloys are produced to obtain some desirable quality; such as, greater hardness, strength, lightness, or durability.

A substance which has metallic properties, and that consists of two or more elements; usually, at least one of which is a metal.

Alloys have been known since virtually the beginning of recorded history; a prehistoric age, in fact, is known as the Bronze Age, indicating the advent of human's ability to smelt bronze, an alloy of copper and tin.

Other well-known alloys include brass, an alloy of copper and zinc; and steel, an alloy of iron and carbon.

Alloys have been created by mixing metals with semi-metals like arsenic and antimony and with nonmetals like carbon and silicon.

Most alloys are developed for a specific physical characteristic; such as, malleability or strength.