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Related to secretion: tubular secretion

se·cre·tion 1

1. The process of secreting a substance, especially one that is not a waste, from the blood or cells: secretion of hormones; secretion of milk by the mammary glands.
2. A substance, such as saliva, mucus, tears, bile, or a hormone, that is secreted.

[French sécrétion, from Old French, separation, from Latin sēcrētiō, sēcrētiōn-, from sēcrētus, past participle of sēcernere, to set aside; see secern.]

se·cre′tion·ar′y (-shə-nĕr′ē) adj.

se·cre·tion 2

1. The act of concealing something in a hiding place.
2. The act of stealing something secretly.

[From secrete.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Biology) a substance that is released from a cell, esp a glandular cell, and is synthesized in the cell
2. (Biology) the process involved in producing and releasing such a substance from the cell
[C17: from Medieval Latin sēcrētiō, from Latin: a separation; see secern]
seˈcretionary adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(sɪˈkri ʃən)

1. (in a cell or gland) the process of separating, elaborating, and releasing a substance that fulfills some function within the organism or undergoes excretion.
2. the product of this process.
[1640–50; < Latin sēcrētiō separation, derivative of sēcrē-, variant s. of sēcernere (see secern)]
se•cre′tion•ar`y (-ʃəˌnɛr i) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


  • gall - As in gallbladder, it refers to a secretion of the liver or to bile.
  • honeyflow - The period of secretion of honey or nectar by flowers.
  • sepia - A cuttlefish, the origin of the brown pigment prepared from a secretion of the fish.
  • larp - The secretion from eucalyptus.
Farlex Trivia Dictionary. © 2012 Farlex, Inc. All rights reserved.


The natural production and release of a useful substance.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.secretion - the organic process of synthesizing and releasing some substance
galactosis - the secretion of milk
hypersecretion - excessive secretion
biological process, organic process - a process occurring in living organisms
salivation - the secretion of saliva
2.secretion - a functionally specialized substance (especially one that is not a waste) released from a gland or cell
ganoin, ganoine - shiny substance that resemble enamel and is secreted by the corium of certain fishes (especially ganoid fishes) and composes the outer layer of their scales
bodily fluid, body fluid, liquid body substance, humour, humor - the liquid parts of the body
lachrymal secretion, lacrimal secretion - saline fluid secreted by lacrimal glands; lubricates the surface of the eyeball
perspiration, sudor, sweat - salty fluid secreted by sweat glands; "sweat poured off his brow"
endocrine, hormone, internal secretion - the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect
intestinal juice - secretions by glands lining the walls of the intestines
autacoid, autocoid - any physiologically active internal secretion especially one of uncertain classification
synovia, synovial fluid - viscid lubricating fluid secreted by the membrane lining joints and tendon sheaths etc.
mucous secretion, mucus - protective secretion of the mucus membranes; in the gut it lubricates the passage of food and protects the epithelial cells; in the nose and throat and lungs it can make it difficult for bacteria to penetrate the body through the epithelium
saliva, spittle, spit - a clear liquid secreted into the mouth by the salivary glands and mucous glands of the mouth; moistens the mouth and starts the digestion of starches
sebum - the oily secretion of the sebaceous glands; with perspiration it moistens and protects the skin
royal jelly - a secretion of the pharyngeal glands of bees that is fed to very young larvae and to bees destined to be queens
musk - an odorous glandular secretion from the male musk deer; used as a perfume fixative
nectar - a sweet liquid secretion that is attractive to pollinators
pheromone - a chemical substance secreted externally by some animals (especially insects) that influences the physiology or behavior of other animals of the same species
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


noun discharge, emission, excretion, exudation, extravasation (Medical) the secretion of adrenaline
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002
إفْرازإفْراز، مادَّه مُفْرَزَه


[sɪˈkriːʃən] N
1. (Med) → secreción f
2. (= hiding) → ocultación f
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


[sɪˈkriːʃən] n [plant, animal, human] → sécrétion f
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


(= hiding)Verbergen nt
(Med: = act) → Absonderung f, → Sekretion f; (= substance)Sekret nt
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[sɪˈkriːʃn] nsecrezione f
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(siˈkriːt) verb
1. (of a gland or similar organ of the body) to separate (a fluid) from the blood, store it, and give it out. The liver secretes bile.
2. to hide. He secreted the money under his mattress.
seˈcretion (-ʃən) noun
1. the process of secreting a fluid.
2. a substance produced by this process. Saliva and urine are secretions.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.


n. secreta, sustancia segregada por una célula, tejido u órgano.
English-Spanish Medical Dictionary © Farlex 2012


n secreción f
English-Spanish/Spanish-English Medical Dictionary Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
References in classic literature ?
Tears are scientifically described as a Secretion. I can understand that a secretion may be healthy or unhealthy, but I cannot see the interest of a secretion from a sentimental point of view.
Louis thinks they were accompanied by an increased secretion of tears.
"My worthy Ned," I answered, "to the poet, a pearl is a tear of the sea; to the Orientals, it is a drop of dew solidified; to the ladies, it is a jewel of an oblong shape, of a brilliancy of mother-of-pearl substance, which they wear on their fingers, their necks, or their ears; for the chemist it is a mixture of phosphate and carbonate of lime, with a little gelatine; and lastly, for naturalists, it is simply a morbid secretion of the organ that produces the mother-of-pearl amongst certain bivalves."
Besides this means of defence, an acrid secretion, which is spread over its body, causes a sharp, stinging sensation, similar to that produced by the Physalia, or Portuguese man-of-war.
Then in the case of excisions you have all kinds of secondary changes, pigmentary disturbances, modifications of the passions, alterations in the secretion of fatty tissue.
Their clothes and their letters reek with the foetid secretion of the musk deer.
The most interesting part of Cannon's book consists in the investigation of the effects produced by secretion of adrenin.
A cerebral secretion that enables one having it to know a house from a horse by the roof on the house.
Pedunculated cirripedes have two minute folds of skin, called by me the ovigerous frena, which serve, through the means of a sticky secretion, to retain the eggs until they are hatched within the sack.
For the fact that, from the point of view of observation, reason and the will are merely secretions of the brain, and that man following the general law may have developed from lower animals at some unknown period of time, only explains from a fresh side the truth admitted thousands of years ago by all the religious and philosophic theories- that from the point of view of reason man is subject to the law of necessity; but it does not advance by a hair's breadth the solution of the question, which has another, opposite, side, based on the consciousness of freedom.
And he went without shrinking through his abstinence from drugs, much sustained by application of the thermometer which implied the importance of his temperature, by the sense that he furnished objects for the microscope, and by learning many new words which seemed suited to the dignity of his secretions. For Lydgate was acute enough to indulge him with a little technical talk.
Her ladyship's correspondence and visiting list, her ladyship's household bills and ledgers; her ladyship's Diary and Memorandum-book (bound in scarlet morocco); her ladyship's desk, envelope-case, match-box, and taper candlestick (all in ebony and silver); her ladyship herself, presiding over her responsibilities, and wielding her materials, equal to any calls of emergency, beautifully dressed in correct morning costume, blessed with perfect health both of the secretions and the principles; absolutely void of vice, and formidably full of virtue, presented, to every properly-constituted mind, the most imposing spectacle known to humanity--the British Matron on her throne, asking the world in general, When will you produce the like of Me?