alkali

[ al-kuh-lahy ]
/ ˈæl kəˌlaɪ /

noun, plural al·ka·lis, al·ka·lies.

Chemistry.
  1. any of various bases, the hydroxides of the alkali metals and of ammonium, that neutralize acids to form salts and turn red litmus paper blue.
  2. any of various other more or less active bases, as calcium hydroxide.
  3. (not in technical use) an alkali metal.
  4. Obsolete. any of various other compounds, as the carbonates of sodium and potassium.
Agriculture. a soluble mineral salt or a mixture of soluble salts, present in some soils, especially in arid regions, and detrimental to the growing of most crops.

adjective

Chemistry. alkaline.

Origin of alkali

1300–50; Middle English alkaly < Middle French alcali < dialectal Arabic al-qalī, variant of Arabic qily saltwort ashes

Example sentences from the Web for alkali

British Dictionary definitions for alkali

alkali
/ (ˈælkəˌlaɪ) /

noun plural -lis or -lies

chem a soluble base or a solution of a base
a soluble mineral salt that occurs in arid soils and some natural waters

Word Origin for alkali

C14: from Medieval Latin, from Arabic al-qili the ashes (of the plant saltwort)

Medical definitions for alkali

alkali
[ ălkə-lī′ ]

n. pl. al•ka•lis

A carbonate or hydroxide of an alkali metal, the aqueous solution of which is bitter, slippery, caustic, and characteristically basic in reactions.
Any of various soluble mineral salts found in natural water and arid soils.
Alkali metal.

Scientific definitions for alkali

alkali
[ ălkə-lī′ ]

Plural alkalis alkalies

A hydroxide of an alkali metal. The aqueous solution of alkalis is bitter, slippery, caustic, and characteristically basic in reactions.

Cultural definitions for alkali

alkali
[ (al-kuh-leye) ]

A bitter, caustic mineral often found in large beds in the desert. Alkalis are bases; two common examples are lye and ammonia.

notes for alkali

Plants have difficulty growing in soil that is rich in alkalis.