WordReference Random House Learner's Dictionary of American English © 2026
a•lu•mi•num /əˈlumənəm/USA pronunciation
n. [uncountable]
WordReference Random House Unabridged Dictionary of American English © 2026- Chemistrya silver-white metallic element, light in weight and not easily corroded or tarnished, used in alloys and for lightweight products.
a•lu•mi•num
(ə lo̅o̅′mə nəm),USA pronunciation n.
adj.
al•u•min•ic
(al′yə min′ik),USA pronunciation adj.
- Chemistrya silver-white metallic element, light in weight, ductile, malleable, and not readily corroded or tarnished, occurring combined in nature in igneous rock, shale, clay, and most soil: used in alloys and for lightweight utensils, castings, airplane parts, etc. Abbr.: alum.; Symbol: Al;
at. wt.: 26.98;
at. no.: 13;
sp. gr.: 2.70 at 20°C.
adj.
- Chemistryof, pertaining to, or containing aluminum:an aluminum frying pan.Also,[esp. Brit.,] aluminium.
- Neo-Latin, alteration, by Humphry Davy, of alumium, which was first proposed; aluminium formed after other metals in -ium. See alumina, -ium
- 1812
'aluminic' also found in these entries (note: many are not synonyms or translations):