cryp·​to·​spo·​rid·​i·​um ˌkrip-tō-spȯr-ˈi-dē-əm How to pronounce cryptosporidium (audio)
plural cryptosporidia ˌkrip-tō-spȯr-ˈi-dē-ə How to pronounce cryptosporidium (audio)
: any of a genus (Cryptosporidium of the order Coccidia) of protozoans parasitic in the gut of vertebrates including humans and sometimes causing diarrhea

Examples of cryptosporidium in a Sentence

Recent Examples on the Web These diseases include bacterial infections like campylobacter and salmonella and parasitic infections like cryptosporidium, giardia and tapeworm. Symptoms can include abdominal cramping, diarrhea, fever and vomiting. Katia Hetter, CNN, 29 Feb. 2024 Construction on the tunnels began in 1981 and the system was up and running in the fall of 1993, months after the city faced a cryptosporidium outbreak, the U.S.’s largest outbreak of waterborne illness to this day. Caitlin Looby, Journal Sentinel, 11 Jan. 2024 The micro-filtration membrane removes waterborne bacteria (including E. coli and salmonella) as well as waterborne parasites (including giardia and cryptosporidium) to provide up to 1,000 gallons of clean, safe drinking water when used properly. Alesandra Dubin, Travel + Leisure, 2 Jan. 2024 The longest emergency groundwater use happened in 2017 for 31 days due to the detection of cryptosporidium, a potentially disease-causing microorganism. Gwozniac, oregonlive, 8 Sep. 2023 The microorganisms, toxoplasma gondii, cryptosporidium parvum and giardia enterica, end up in waterways when feces from infected animals contaminate the water. Laura L. Davis, USA TODAY, 28 Apr. 2022 This includes testing for the presence of dangerous contaminants like E. coli, salmonella, and cryptosporidium. Justin Klawans, The Week, 10 June 2023 Children playing in the yard and adults gardening are particularly at risk of picking up diseases and parasites like campylobacteriosis, cryptosporidium and toxocariasis, the agency warns. Dallas News, 3 May 2022 Oocysts of cryptosporidium stained using the Ziehl-Nielson stain. Rebecca Kreston, Discover Magazine, 26 May 2014

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cryptosporidium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


borrowed from New Latin, genus name, from crypto- crypto- + sporidium "small spore," from spora spore entry 1 + -idium -idium

Note: Taxon introduced by the American physician and parasitologist Ernest E. Tyzzer (1875-1965) in "A sporozoan found in the peptic glands of the common mouse," Proceedings of the Society for Experimental Biology and Medicine, vol. 5 (1907-08), pp. 12-13.

First Known Use

1910, in the meaning defined above

Time Traveler
The first known use of cryptosporidium was in 1910

Dictionary Entries Near cryptosporidium

Cite this Entry

“Cryptosporidium.” Dictionary, Merriam-Webster, Accessed 18 May. 2024.

Medical Definition


cryp·​to·​spo·​rid·​i·​um ˌkrip-tō-spȯr-ˈid-ē-əm How to pronounce cryptosporidium (audio)
capitalized : a genus of protozoans of the order Coccidia that are parasitic in the gut of many vertebrates including humans and that sometimes cause diarrhea especially in individuals who are immunocompromised (as in AIDS)
plural cryptosporidia -ē-ə How to pronounce cryptosporidium (audio) : any protozoan of the genus Cryptosporidium
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