Hypertext Webster Gateway: "pentacid"
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Pentacid \Pen*tac"id\, a. [Penta- + acid.] (Chem.)
Capable of neutralizing, or combining with, five molecules of
a monobasic acid; having five hydrogen atoms capable of
substitution by acid residues; -- said of certain complex
bases.
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