• 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.
Show More
verb (used without object), sa·pon·i·fied, sa·pon·i·fy·ing.
  1. to become converted into soap.
Show More

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 saponify

Historical Examples

  • Next to olive oil, this species is the most easy to saponify.

    A Dictionary of Arts, Manufactures and Mines

    Andrew Ure

  • But to simplify the operation, he preferred to saponify the fat by means of lime.

  • This oil closely resembles cocoa-nut and palm-nut oils and is stated to saponify readily and yield a soap free from odour.

  • Caustic soda is then added to saponify the fat not converted by the lime saponification.

    Soap-Making Manual

    E. G. Thomssen

  • First saponify 100 parts house grease and 100 parts ordinary grease and make a run soap.

    Soap-Making Manual

    E. G. Thomssen

British Dictionary definitions for saponify


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
Show More
Derived Formssaponifiable, adjectivesaponifier, nounsaponification, noun

Word Origin

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 saponify


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

Show More
Online Etymology Dictionary, © 2010 Douglas Harper

saponify in Medicine


  1. To undergo saponification.
Show More
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.