Anion

Part of speech: noun

Pronunciation: /ˈænˌaɪ.ən/

Definitions

1. A negatively charged ion that is attracted to the positive electrode in an electrochemical cell
2. A type of ion that carries a negative charge and migrates towards positively charged electrodes in electrochemical reactions
3. This ion, which possesses a negative electrical charge, moves to the anode during electrochemical processes

Etymology: The word was coined in 1834 by William Whewell, a Cambridge polymath, for the physicist Michael Faraday, who introduced it to the scientific world later that same year. Faraday needed names for the two kinds of charged particle that travel through a liquid during electrolysis, and Whewell, who was advising him on terminology, built them from Ancient Greek. "Ion" itself was Faraday's coinage, taken from the Greek verb "ienai," meaning "to go," so an ion is literally a "goer." "Anion" combines "ion" with the Greek "anion," the neuter present participle of "aneimi," meaning "to go up," from "ana" ("up") and "eimi" ("go"). The name reflects Faraday's observation that these negatively charged particles move toward the anode, the positive electrode, so they were the ones "going up." Its partner, "cation," was formed the same way from the Greek for "going down," which refers to particles moving toward the cathode.

Synonyms: negatively charged ion, anion species, negative ion, charge carrier, electrolyte