Chem. [f. ARS-ENIC + termination of AMMONIUM.] A name applied (chiefly in combination) to a univalent organic arsenic radical, analogous in composition to ammonium and phosphonium, as tetramethyl-arsonium As(CH3)4 Hence Arsonic a., pertaining to arsonium; applied to a group of acids, analogous to the phosphonic acids (Fownes).
