aluminum

noun

alu·​mi·​num ə-ˈlü-mə-nəm 

: a silver-white metallic chemical element with atomic number 13 that has good electrical and thermal conductivity, high reflectivity, and resistance to oxidation

—often used before another noun

aluminum foil

The sweet spot, the point in a bat where vibration supposedly is least, is said to be two times larger on an aluminum bat than on a wood one.

—Hank Hersch

Before he evacuated, Mr. Gonzales tied the boat down with four gigantic ropes and all the storm could do was knock it off the construction blocks. He slowly climbs a battered aluminum ladder propped up on the port side.

—Ken Wells

see Chemical Elements Table

Examples of aluminum in a Sentence

Recent Examples on the Web

The president has slapped a 10% duty on all imports, along with an additional 30% levy on goods from China, 50% on steel and aluminum, and 25% on autos. —Arkansas Online, 25 June 2025

Trump has slapped a 10% duty on all imports, along with an additional 30% levy on goods from China, 50% on steel and aluminum, and 25% on autos. —Preston Fore, Fortune, 24 June 2025

Hers is a bewitching world in which nephrite jade cacti rings vie for space with anodized aluminum pot plant earrings, and punchy lozenges of blue chalcedony and faceted smoky quartz. —Kate Matthams, Forbes.com, 24 June 2025

Yet for all its sheer matter—steel, glass, silver, aluminum, copper, ferroconcrete, silicon—the observatory seems to lift off into a mytho-poetic dimension. —Michael Jones McKean, The Atlantic, 23 June 2025

Word History

Etymology

alumine "alumina" (borrowed from French, borrowed from Latin alūmin-, alūmen alum entry 1) + -um (in the names of other metals, as platinum entry 1, tantalum)

First Known Use

1812, in the meaning defined above

Phrases Containing aluminum

• aluminum foil
• aluminum oxide
• aluminum sulfate

Rhymes for aluminum

• aluminium

Kids Definition

aluminum

noun

alu·​mi·​num ə-ˈlü-mə-nəm 

: a silver-white malleable light element that conducts electricity and heat well, is highly resistant to oxidation, and is the most abundant metal in the earth's crust see element

Medical Definition

aluminum

noun

alu·​mi·​num ə-ˈlü-mə-nəm 

: a silver-white malleable ductile light trivalent metallic chemical element with atomic number 13 that has good electrical and thermal conductivity, high reflectivity, and resistance to oxidation

—symbol Al see Chemical Elements Table