dialysis

noun

di·​al·​y·​sis dī-ˈa-lə-səs How to pronounce dialysis (audio)
plural dialyses dī-ˈa-lə-ˌsēz How to pronounce dialysis (audio)
1
: the separation of substances in solution by means of their unequal diffusion through semipermeable membranes
especially : such a separation of colloids from soluble substances
2
: the process of removing blood from an artery (as of a patient affected with kidney failure), purifying it by dialysis, adding vital substances, and returning it to a vein

called also hemodialysis

dialytic
ˌdī-ə-ˈli-tik How to pronounce dialysis (audio)
adjective

Examples of dialysis in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
That's partly because some surgeons have more experience than others using kidneys with complex anatomy such as extra arteries, or those from older, sicker donors that still may be better than dialysis for the right patient. — ABC News, 20 Oct. 2026 Health Resources and Services Administration Administrator Tom Engels said the new plan was focused on ensuring that there was no corruption in the dialysis and transplant systems and stopping monopolies in those systems. — Ciara McCarthy, Fort Worth Star-Telegram, 20 Oct. 2026 However, anyone with CKD, kidney failure, a recent kidney injury, or dialysis treatment should speak with a healthcare provider before taking any supplement. — Md Published, Verywell Health, 14 Oct. 2026 Babacar Dem had been undergoing dialysis three times a week while also driving a cab. — Evan Simko-Bednarski, New York Daily News, 13 Oct. 2026 See All Example Sentences for dialysis

Word History

Etymology

New Latin, from Greek, separation, from dialyein to dissolve, from dia- + lyein to loosen — more at lose

First Known Use

1861, in the meaning defined at sense 1

Time Traveler
The first known use of dialysis was in 1861

Rhymes for dialysis

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Browse Nearby Words

dialyse
dialysis
dialytic
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Cite this Entry

“Dialysis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dialysis. Accessed 25 Oct. 2026.

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Kids Definition

dialysis

noun
di·​al·​y·​sis dī-ˈal-ə-səs How to pronounce dialysis (audio)
plural dialyses -ə-ˌsēz How to pronounce dialysis (audio)
1
: the separation of substances in solution by means of their unequal diffusion through membranes with pores of a specified maximum size
especially : such a separation of colloids from dissolved substances
2
: the process of removing blood from an artery (as of a patient with failing kidneys), purifying it by dialysis, and returning it to a vein

Medical Definition

dialysis

noun
di·​al·​y·​sis dī-ˈal-ə-səs How to pronounce dialysis (audio)
plural dialyses -ˌsēz How to pronounce dialysis (audio)
1
: the separation of substances in solution by means of their unequal diffusion through semipermeable membranes
especially : such a separation of colloids from soluble substances
2
: either of two medical procedures to remove wastes or toxins from the blood and adjust fluid and electrolyte imbalances by utilizing rates at which substances diffuse through a semipermeable membrane:
a
: the process of removing blood from an artery (as of a kidney patient), purifying it by dialysis, adding vital substances, and returning it to a vein

called also hemodialysis

b
: a procedure performed in the peritoneal cavity in which the peritoneum acts as the semipermeable membrane

called also peritoneal dialysis

dialytic
ˌdī-ə-ˈlit-ik How to pronounce dialysis (audio)
adjective

More from Merriam-Webster on dialysis

Britannica.com: Encyclopedia article about dialysis

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