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noun, al·ka·li \ˈal-kə-ˌlī\

Simple Definition of alkali

  • chemistry : a substance that has a bitter taste and that forms a salt when mixed with an acid

Source: Merriam-Webster's Learner's Dictionary

Full Definition of alkali

plural alkalies or alkalis

  1. 1 :  a soluble salt obtained from the ashes of plants and consisting largely of potassium or sodium carbonate; broadly :  a substance (as a hydroxide or carbonate of an alkali metal) having marked basic properties — compare base 7a

  2. 2 :  alkali metal

  3. 3 :  a soluble salt or a mixture of soluble salts present in some soils of arid regions in quantity detrimental to agriculture

Origin of alkali

Middle English, from Medieval Latin, from Arabic al-qili the ashes of the plant saltwort

First Known Use: 14th century

Other Chemical Engineering Terms

Rhymes with alkali

abide by, Adonai, alibi, amplify, apple-pie, argufy, assegai, azo dye, basify, beautify, butterfly, by-and-by, caddis fly, calcify, certify, Chou En-lai, citify, clarify, classify, coalify, cockneyfy, codify, college try, cottage pie, crucify, cut-and-try, cutie-pie, DIY, damnify, damselfly, dandify, deify, densify, dignify, dobsonfly, do-or-die, dragonfly, dulcify, eagle eye, edify, evil eye, falsify, fancify, fortify, frenchify, fructify, gasify, Gemini, gentrify, glorify, goggle-eye, goldeneye, gratify, Haggai, harvest fly, hexerei, high and dry, hip and thigh, Hokusai, hook and eye, horrify, hoverfly, humble pie, Iceni, justify, kiss good-bye, lazy eye, lignify, liquefy, lithify, Lorelei, lullaby, Madurai, magnify, Malachi, Maracay, minify, modify, mollify, Molokai, Mordecai, mortify, multi-ply, multiply, mummify, mystify, nazify, notify, nullify, occupy, old school tie, on standby, on the fly, ossify, overbuy, overfly, overlie, pacify, Paraguay, passerby, peccavi, petrify, PPI, preachify, prettify, private eye, prophesy, purify, putrefy, qualify, quantify, ramify, rarefy, ratify, RBI, rectify, reify, res gestae, robber fly, runner's high, Russify, samurai, sanctify, satisfy, scarify, schwarmerei, semidry, set store by, shepherd's pie, shoofly pie, signify, simplify, Spanish fly, specify, speechify, stratify, stultify, stupefy, sweetie pie, Tenebrae, terrify, testify, tie-and-dye, tigereye, Trans Alai, tumble dry, typify, uglify, underlie, unify, Uruguay, Veneti, verify, versify, vilify, vinify, vitrify, vivify, weather eye, Windsor tie, xanthene dye, yuppify, zombify

ALKALI Defined for Kids


noun al·ka·li \ˈal-kə-ˌlī\

Definition of alkali for Students

plural alkalies or alkalis

  1. 1 :  a substance that has a bitter taste and reacts with an acid to form a salt :  base

  2. 2 :  a salt or a mixture of salts sometimes found in large amounts in the soil of dry regions

Medical Dictionary


noun al·ka·li \ˈal-kə-ˌlī\

Medical Definition of alkali

plural alkalies or alkalis

  1. :  a substance (as a hydroxide or carbonate of an alkali metal) having marked basic properties—compare base

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