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os·mo·sis (ŏz-mōsĭs, ŏs-)
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n. pl. os·mo·ses(-sēz)
1.
a. Diffusion of fluid through a semipermeable membrane from a solution with a low solute concentration to a solution with a higher solute concentration. Osmosis ceases when there is an equal solute concentration on both sides of the membrane.
b. The tendency of fluids to diffuse in such a manner.
2. A gradual, often unconscious process of assimilation or absorption: learned French by osmosis while residing in Paris for 15 years.
[From obsolete osmose, from earlier endosmose, from French : Greek endo-, endo- + Greek ōsmos, thrust, push (from ōthein, to push).]
os·motic (-mŏtĭk) adj.
os·moti·cal·ly adv.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
os·mose (ŏzmōs′, ŏs-)
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intr. & tr.v. os·mosed, os·mos·ing, os·mos·es
To diffuse or cause to diffuse by osmosis.
[Back-formation from OSMOSIS.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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