Webster's Revised Unabridged Dictionary · 1913

Anion

Anion ({not transcribed}) , noun

[Greek {not transcribed}, neut. {not transcribed}, present participle of {not transcribed} to go up; {not transcribed} up + {not transcribed} to go.]

(Chemistry) An electro-negative atom or group of atoms, or the element which, in electro-chemical decompositions, is evolved at the anode; -- opposed to cation. — Faraday