sulfur

1. (uncountable) A chemical element (symbol S) with an atomic number of 16, having a bright yellow color and characteristic smell, used commercially in a variety of products such as insecticides, black powder, and matchsticks.Examples: "A Dungeon horrible, on all ſides round / As one great Furnace flam’d, yet from thoſe flames / No light, but rather darkneſs viſible / […] but torture without end / Still urges, and a fiery Deluge, fed / With ever-burning Sulphur unconſum’d:"; "Sure only that man is mortal; that with the life of one mortal snaps irrevocably the wonderfulest talisman, and all Dubarrydom rushes off, with tumult, into infinite Space; and ye, as subterranean Apparitions are wont, vanish utterly,—leaving only a smell of sulphur!"; "Scarcely had these manifestations ceased at Ustica, than Vesuvius began to show signs of increased activity; the supplies in the wells on the mountain sides began to fail, and there was observed a strong taste of sulphur in the drinking water; whilst—most dreaded phenomenon of all—the ever-active crater of Stromboli, that lies midway between Naples and Messina, suddenly lapsed into quiescence."Synonyms: brimstoneuncountableusually

2. (countable, uncountable) A yellowish green colour, like that of sulfur.countableuncountableusually