Secretion or formation of milk by the mammary glands.(noun)
The period during which the mammary glands secrete milk.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "lactation" in a sentence
"As he took mental notes on the relevant biology and process, a curious Flinx could not keep from mentally substituting the term lactation for secretion, even though nothing about the practice had anything to do with milk."
"According to Newman, lactation is listed as a possible side effect of the heart medication digoxin."
"Male lactation is most commonly caused by hormonal treatments given to men suffering from prostate cancer."