Pronunciation: (sul'fur),[key] —n. 1. Also,esp. Brit.,sulphur.Chem.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 esp. in making gunpowder and matches, in medicine, in vulcanizing rubber, etc. Symbol: S; at. wt.: 32.064; at. no.: 16; sp. gr.: 2.07 at 20° C.
2. sulphur (def. 2).