[lak-tey-shuh n]


the secretion or formation of milk.
the period of milk production.

Origin of lactation

1660–70; < Late Latin lactātiōn- (stem of lactātiō) a giving suck. See lactate1, -ion
Related formslac·ta·tion·al, adjectivelac·ta·tion·al·ly, adverbhy·per·lac·ta·tion, nouno·ver·lac·ta·tion, nounsu·per·lac·ta·tion, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for lactation

suction, lactation

Examples from the Web for lactation

Contemporary Examples of lactation

Historical Examples of lactation

British Dictionary definitions for lactation



the secretion of milk from the mammary glands after parturition
the period during which milk is secreted
Derived Formslactational, adjectivelactationally, adverb
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 lactation

1660s, "process of suckling an infant," from French lactation, from Late Latin lactationem (nominative lactatio) "a suckling," noun of action from past participle stem of lactare "suckle," from lac (genitive lactis) "milk," from PIE root *glakt- (cf. Greek gala, genitive galaktos, "milk"), which, along with *melg-, accounts for words for "milk" in most Indo-European languages (the absence of a common word for it is considered a mystery). Meaning "process of secreting milk from the breasts" first recorded 1857. Middle Irish lacht, Welsh llaeth "milk" are loan words from Latin.

Online Etymology Dictionary, © 2010 Douglas Harper

lactation in Medicine




The secretion or formation of milk by the mammary glands.
The period during which the mammary glands secrete milk.
Related formslac•tation•al adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

lactation in Science



The secretion or production of milk by the mammary glands in female mammals after giving birth.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.