Pronunciation: (floor'ēn, -in, flôr'-, flōr'-), [key]
the most reactive nonmetallic element, a pale-yellow, corrosive, toxic gas that occurs combined, esp. in fluorite, cryolite, phosphate rock, and other minerals. Symbol: F; at. wt.: 18.9984; at. no.: 9.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.