1) Chemical nomenclature 
• (a.) Capable of neutralizing, or of combining with, several molecules of a monacid base; having several hydrogen atoms capable of being replaced by basic radicals; -- said of certain acids; as, sulphuric acid is polybasic.
(pol″e-ba´sik) having several replaceable hydrogen atoms.
Pol`y·ba'sic adjective [ Poly- + basic .] (Chemistry) Capable of neutralizing, or of combining with, several molecules of a monacid base; having several hydrogen atoms capable of being replaced by basic radicals; -- said of certain acids; as, sulphuric acid is polybasic . 
Type: Term Pronunciation: pol′ē-bā′sik Definitions: 1. Having more than one replaceable hydrogen atom, denoting an acid with a basicity greater than 1.