a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatite
The chemical element (symbol F) with an atomic number of 9. It is the lightest of the halogens, a pale yellow-green, highly reactive gas that attacks all metals.
The name fluorine comes from the Latin word fluor, meaning "to flow," combined with the suffix -ine. British chemist Humphry Davy coined this term in 1813.