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 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.
Those who develop hemorrhagic fever with renal syndrome may need hospitalization and dialysis to help their body remove toxins if their kidneys become affected or damaged. Mary Walrath-Holdridge, USA Today, 7 May 2026 The bank upgraded the dialysis service provider to buy from hold. Liz Napolitano, CNBC, 6 May 2026 Individuals with complications such as hemorrhagic fever and renal syndrome require close monitoring of kidney function and may need dialysis. Tom Gavin, EverydayHealth.com, 5 May 2026 He was placed on dialysis, but his condition continued to decline. Lexi Lane, PEOPLE, 2 May 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

Browse Nearby Words

Cite this Entry

“Dialysis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dialysis. Accessed 13 May. 2026.

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 adjective

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