oocyst

noun

oo·​cyst ˈō-ə-ˌsist How to pronounce oocyst (audio)
: zygote
specifically : a sporozoan zygote undergoing sporogenous development

Examples of oocyst 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.
Once released, an oocyst can persist in soil or water for years. — Gustavo Arrizabalaga and Bill Sullivan, Scientific American, 1 Mar. 2015 When an infected or recently sick swimmer takes a dip, oocysts can enter the pool. — Beth Mole, Ars Technica, 26 Oct. 2023 Changing the litter box daily ensures that the oocysts will not become a danger. — Bill Sullivan, Discover Magazine, 2 Jan. 2024 The parasite’s eggs, called oocysts, are shed in cat stool and can contaminate soil, water and food. — Dr. Megan Yanny, Boston Herald, 31 May 2026 Southern sea otters are commonly exposed through their diet, eating clams and other filter-feeding invertebrates that contain the oocysts. — Byerik Stokstad, science.org, 22 Mar. 2023 Free-range animals are more prone to pick up infectious Toxoplasma oocysts in outdoor pastures and water sources, which have a higher likelihood of being contaminated with cat feces. — Bill Sullivan, The Conversation, 10 July 2024

Word History

Etymology

International Scientific Vocabulary

First Known Use

1875, in the meaning defined above

Time Traveler
The first known use of oocyst was in 1875

Rhymes for oocyst

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Browse Nearby Words

oocapt
oocyst
Oocystaceae
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Cite this Entry

“Oocyst.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/oocyst. Accessed 7 Jul. 2026.

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Medical Definition

oocyst

noun
oo·​cyst ˈō-ə-ˌsist How to pronounce oocyst (audio)
: zygote
specifically : a sporozoan zygote undergoing sporogenous development

More from Merriam-Webster on oocyst

Britannica.com: Encyclopedia article about oocyst

Last Updated: - Updated example sentences
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