antimony

American  

[an-tuh-moh-nee] / ˈæn təˌmoʊ ni /

noun

Chemistry.

1. a brittle, lustrous, white metallic element occurring in nature free or combined, used chiefly in alloys and in compounds in medicine. Sb; 51; 121.75.

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antimony British  

/ ˈæntɪmənɪ /

noun

1. a toxic metallic element that exists in two allotropic forms and occurs principally in stibnite. The stable form is a brittle silvery-white crystalline metal that is added to alloys to increase their strength and hardness and is used in semiconductors. Symbol: Sb; atomic no: 51; atomic wt: 121.757; valency: 0, –3, +3, or +5; relative density: 6.691; melting pt: 630.76°C; boiling pt: 1587°C

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antimony Scientific  

/ ăn′tə-mō′nē /

1. A metalloid element having many forms, the most common of which is a hard, very brittle, shiny, blue-white crystal. It is used in a wide variety of alloys, especially with lead in car batteries, and in the manufacture of flameproofing compounds. Atomic number 51; atomic weight 121.76; melting point 630.5°C (1,167°F); boiling point 1,380°C (2,516°F); specific gravity 6.691; valence 3, 5.

2. See Periodic Table

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Other Word Forms

Derived Forms

• antimonial
  adjective

Etymology

Origin of antimony

1375–1425; late Middle English antimonie < Medieval Latin antimōnium, perhaps < dialectal Arabic uthmud

Example Sentences

Sunshine Silver Mining & Refining, which also mines copper and antimony, a flame retardant mineral, could be a backdoor AI play given the demand for wiring in data centers.

From Barron's • Jun. 2, 2026

In October, China's Ministry of Commerce announced new restrictions on exports of silver as well as the metals tungsten and antimony to "to step up the protection of resources and the environment".

From BBC • Dec. 30, 2025

Elevated amounts of lead, chromium, and antimony were also detected.

From Science Daily • Nov. 28, 2025

Blakestad’s employer, United States Antimony, operates an antimony smelter in the U.S.

From The Wall Street Journal • Nov. 8, 2025

The money was not altogether wasted—new chemical elements, such as phosphorus, antimony and mercury, were discovered.

From "Cosmos" by Carl Sagan