• synonyms


verb (used with object), sa·pon·i·fied, sa·pon·i·fy·ing.
  1. to convert (a fat) into soap by treating with an alkali.
  2. to decompose (any ester), forming the corresponding alcohol and acid or salt.
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verb (used without object), sa·pon·i·fied, sa·pon·i·fy·ing.
  1. to become converted into soap.
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Origin of saponify

1815–25; < Latin sāpōn- (stem of sāpō) soap + -ify
Related formssa·pon·i·fi·a·ble, adjectivesa·pon·i·fi·ca·tion, nounsa·pon·i·fi·er, nounnon·sa·pon·i·fi·a·ble, adjectivenon·sa·pon·i·fi·ca·tion, nounun·sa·pon·i·fi·a·ble, adjectiveun·sa·pon·i·fied, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for saponification

Historical Examples of saponification

  • For the saponification we employ a solution of sodium ethylate in the cold.

    Researches on Cellulose

    C. F. Cross

  • The commencement of the saponification is denoted by the formation of an emulsion.

  • Hence it does not contain a soap, and is not a saponification of fat.

  • This is obtained from stearin (see below), by saponification.

  • Carbon Dioxide, Formation of in carbonate saponification, 45.

    Soap-Making Manual

    E. G. Thomssen

British Dictionary definitions for saponification


verb -fies, -fying or -fied chem
  1. to undergo or cause to undergo a process in which a fat is converted into a soap by treatment with alkali
  2. to undergo or cause to undergo a reaction in which an ester is hydrolysed to an acid and an alcohol as a result of treatment with an alkali
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Derived Formssaponifiable, adjectivesaponifier, nounsaponification, noun

Word Origin for saponify

C19: from French saponifier, from Latin sāpō soap
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for saponification


1801, from French saponification, from saponifier, from Modern Latin saponificare, from sapon- "soap" (see soap (n.)) + -ficare, from Latin facere "to make, do" (see factitious).

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1821, from French saponifier (see saponification). Related: Saponified; saponifying.

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Online Etymology Dictionary, © 2010 Douglas Harper

saponification in Medicine


  1. A reaction in which an ester is heated with an alkali, such as sodium hydroxide, producing a free alcohol and an acid salt, especially alkaline hydrolysis of a fat or oil to make soap.
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  1. To undergo saponification.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.