os·mo·sis | \äz-ˈmō-səs, äs-\

Definition of osmosis 

1 : movement of a solvent (such as water) through a semipermeable membrane (as of a living cell) into a solution of higher solute concentration that tends to equalize the concentrations of solute on the two sides of the membrane

2 : a process of absorption or diffusion (see diffusion sense 3a) suggestive of the flow of osmotic action especially : a usually effortless often unconscious assimilation (see assimilation sense 4) learned a number of languages by osmosis — Roger Kimball

Examples of osmosis in a Sentence

She seems to learn foreign languages by osmosis.

Recent Examples on the Web

Dow, for instance, is making reverse-osmosis membranes for water desalination. The Economist, "Breaking the curseWhy Gulf economies struggle to wean themselves off oil," 21 June 2018 Slattery, the show’s restaurant consultant, currently works at wine bar Terroir in TriBeca and taught FitzGerald the art of wine conversation through osmosis. Alyse Whitney, Bon Appetit, "How ‘Sweetbitter’ Compares to Real Fine-Dining Restaurant Training," 10 May 2018 After city testing found high lead levels in the tap water in her Chicago home, Jenny Abrahamian decided to install a whole-house water filtration system and an additional reverse-osmosis filter for her kitchen sink. Michael Hawthorne, chicagotribune.com, "Brain-damaging lead found in tap water in hundreds of homes tested across Chicago, results show," 12 Apr. 2018 Flushed with success, Dr Zhang is now turning his attention to the reverse-osmosis membranes. The Economist, "A membrane that can remove salts from water more efficiently," 3 May 2018 People learn to be racists, Jacobs-Jenkins argues, by some sort of osmosis. Andrea Simakis, cleveland.com, "Dobama Theatre's 'Appropriate' is Long Day's Journey Into White (review)," 26 Apr. 2018 Watch and listen to as many games as possible—to absorb both announcing styles and information via osmosis. Richard Deitsch, SI.com, "Media Circus: 22 Well-Known Sports Media Members Give Advice to Their Younger Selves," 12 Mar. 2018 With unglazed red clay pots, the water may even seep in through the outer walls by osmosis. Maureen Gilmer, idahostatesman, "Consider hand-watering in pots | Idaho Statesman," 28 Feb. 2018 The group has also purchased reverse-osmosis water filtration systems for households that are unable to connect to the municipal water system. Dennis Pillion, AL.com, "Fruithurst well water contains cancer-causing radon, researcher says," 31 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'osmosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of osmosis

1863, in the meaning defined at sense 1

History and Etymology for osmosis

New Latin, short for endosmosis

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Time Traveler for osmosis

The first known use of osmosis was in 1863

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More Definitions for osmosis



English Language Learners Definition of osmosis

biology : the process that causes a liquid (especially water) to pass through the wall of a living cell

: an ability to learn and understand things gradually without much effort


os·mo·sis | \äs-ˈmō-səs, äz-\

Kids Definition of osmosis

: a passing of material and especially water through a membrane (as of a living cell) that will not allow all kinds of molecules to pass


os·mo·sis | \äz-ˈmō-səs, äs- \
plural osmoses\-ˌsēz \

Medical Definition of osmosis 

: movement of a solvent through a semipermeable membrane (as of a living cell) into a solution of higher solute concentration that tends to equalize the concentrations of solute on the two sides of the membrane

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Comments on osmosis

What made you want to look up osmosis? Please tell us where you read or heard it (including the quote, if possible).


a state of commotion or excitement

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