noun, often attributive
alu·​mi·​num | \ ə-ˈlü-mə-nəm How to pronounce aluminum (audio) \

Definition of aluminum

: 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 foilThe 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 HerschBefore 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 outer layer of aluminum reflects approximately 95 percent of this heat, according to Roise. Lou Dzierzak, Scientific American, 25 July 2022 That explains the organic shape of the aluminum casting that forms part of the car's rear structure, which features load paths that no engineer would draw in CAD. Jonathan M. Gitlin, Ars Technica, 24 July 2022 The entry-level Watch is made of aluminum, with higher-end models using stainless steel, titanium or even ceramic. David Phelan, Forbes, 24 July 2022 About 73% of an aluminum can comes from recycled scrap. Los Angeles Times, 16 July 2022 Each quilt square is created with industrial acrylic paint on either a 4-by-4 or 8-by-8-foot piece of composite aluminum for durability. Michelle Matthews |, al, 13 July 2022 Soil pH affects the availability of aluminum for uptake by plant roots. Miri Talabac, Baltimore Sun, 29 June 2022 On a day like Sunday, with the temperature making a run at 90, the idea of sitting on a slab of aluminum for the afternoon will test the will of a lifelong fan and keep marginal ones away. Dave Kallmann, Journal Sentinel, 19 June 2022 Like the conventional model, they’re made of aluminum. Tribune News Service, cleveland, 4 June 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'aluminum.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of aluminum

1812, in the meaning defined above

History and Etymology for aluminum

New Latin, from alumina

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Time Traveler for aluminum

Time Traveler

The first known use of aluminum was in 1812

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Dictionary Entries Near aluminum

aluminous cake


aluminum 26

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Statistics for aluminum

Last Updated

4 Aug 2022

Cite this Entry

“Aluminum.” Dictionary, Merriam-Webster, Accessed 9 Aug. 2022.

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More Definitions for aluminum


alu·​mi·​num | \ ə-ˈlü-mə-nəm How to pronounce aluminum (audio) \

Kids Definition of aluminum

: a silver-white light metallic chemical element that is easily worked, conducts electricity well, resists weathering, and is the most plentiful metal in the earth's crust


noun, often attributive
alu·​mi·​num | \ ə-ˈlü-mə-nəm How to pronounce aluminum (audio) \

Medical Definition of aluminum

: a bluish silver-white malleable ductile light trivalent metallic element that has good electrical and thermal conductivity, high reflectivity, and resistance to oxidation and is the most abundant metal in the earth's crust where it always occurs in combination symbol Al — see Chemical Elements Table

More from Merriam-Webster on aluminum

Nglish: Translation of aluminum for Spanish Speakers

Britannica English: Translation of aluminum for Arabic Speakers Encyclopedia article about aluminum


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