fluorine vs. fluoride

noun

Chemistry.
  1. the most reactive nonmetallic element, a pale-yellow, corrosive, toxic gas that occurs combined, especially in fluorite, cryolite, phosphate rock, and other minerals. F; 18.9984; 9.

noun

Chemistry.
  1. a salt of hydrofluoric acid consisting of two elements, one of which is fluorine, as sodium fluoride, NaF.

  2. a compound containing fluorine, as methyl fluoride, CH 3 F.