n. pl. al·ka·lis or al·ka·lies
1. A carbonate or hydroxide of an alkali metal, the aqueous solution of which is bitter, slippery, caustic, and characteristically basic in reactions.
2. Any of various soluble mineral salts found in natural water and arid soils.
3. Alkali metal.
4. A substance having highly basic properties; a strong base.
[Middle English, alkaline substance from calcined plant ashes, from Medieval Latin, from Arabic al-qily, the ashes, lye, potash : al-, the + qily, ashes (from qalā, to fry, roast; see qly in the Appendix of Semitic roots).]
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