sulfur

American  

[suhl-fer] / ˈsʌl fər /

noun

1. Chemistry. Also a nonmetallic element that exists in several forms, the ordinary one being a yellow rhombic crystalline solid, and that burns with a blue flame and a suffocating odor: used especially in making gunpowder and matches, in medicine, in vulcanizing rubber, etc. S; 32.064; 16; 2.07 at 20° C.

2. sulphur.

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sulfur British  

/ ˈsʌlfə /

noun

1. the US preferred spelling of sulphur

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sulfur Scientific  

/ sŭl′fər /

1. A pale-yellow, brittle nonmetallic element that occurs widely in nature, especially in volcanic deposits, minerals, natural gas, and petroleum. It is used to make gunpowder and fertilizer, to vulcanize rubber, and to produce sulfuric acid. Atomic number 16; atomic weight 32.066; melting point (rhombic) 112.8°C; (monoclinic) 119.0°C; boiling point 444.6°C; specific gravity (rhombic) 2.07; (monoclinic) 1.957; valence 2, 4, 6.

2. See Periodic Table

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Etymology

Origin of sulfur

1300–50; Middle English sulphur < Latin sulpur, sulphur, sulfur brimstone, sulfur

Example Sentences

That year, Parish emitted 42,689 tons of sulfur dioxide, about 16% more than last year.

From The Wall Street Journal • May 21, 2026

Oil-rich countries such as Iran, Kuwait, Qatar, Saudi Arabia and the U.A.E. produced almost a quarter of the world’s supply of sulfur last year, according to a report from the Congressional Research Service, the U.S.

From MarketWatch • May 12, 2026

Some fossil samples contained pyrite, a mineral made of iron and sulfur.

From Science Daily • May 12, 2026

Net sales reach $3 billion, exceeding estimates, but volatile conditions and record sulfur prices impacted input costs.

From Barron's • May 11, 2026

The scent of sulfur became acrid and choking.

From "The City Beautiful" by Aden Polydoros