阴离子
Anion \An"i*on\, n. [Gr. ?, neut. ?, p. pr. of ? to go up; ? up + ? to go.] (Chem.) An electro-negative element, or the element which, in electro-chemical decompositions, is evolved at the anode; -- opposed to {cation}. --Faraday.
anion n : a negatively charged ion