n. 1. See potassium carbonate. 2. See potassium hydroxide. 3. Any of several compounds containing potassium, especially soluble compounds such as potassium oxide, potassium chloride, and various potassium sulfates, used chiefly in fertilizers. [From sing. of obsolete pot ashes, an alkaline substance obtained by leaching wood ashes and evaporating the leachate in a pot.] |
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