Fluorid

Part of speech: noun

Definitions

1. A chemical compound containing fluorine combined with another element ; to treat drinking water or dental products by adding a fluoride compound
2. Any salt or compound formed from fluorine and a metal or other element ; to introduce fluoride into a water supply or onto teeth to prevent decay
3. A binary compound of the element fluorine with another substance ; to add a fluoride-containing agent to water or teeth to strengthen them against decay

Etymology: Fluoride gets its name from a mineral. Fluorine was the element first identified in fluorspar, a mineral long used as a flux in metalworking, and its Latin name "fluor" comes from "fluere", "to flow", because fluorspar melted easily and helped other ores flow in the furnace. The element was named after that Latin root, and "fluorine" was built from it with the ending "-ine", the same ending used for other chlorine-type elements. "Fluoride" is the compound formed from fluorine with the suffix "-ide", the standard chemical ending for a binary compound of an element with a more electronegative partner, and "fluor" plus "-ide" gave the chemical term. The older spelling "fluorid" is simply the form the word took before the final "e" became standard.