spi·​ro·​chete | \ˈspī-rə-ˌkēt \
variants: or less commonly spirochaete

Definition of spirochete 

: any of an order (Spirochaetales) of slender spirally undulating bacteria including those causing syphilis and Lyme disease

Examples of spirochete in a Sentence

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Infected ticks need to be attached 24 to 72 hours before transmission of the spirochete [bacteria] occurs. Andrea K. Mcdaniels, baltimoresun.com, "Ask the expert: With Lyme disease on the rise, here's how you can protect yourself," 3 July 2018 The director of the CAES tick testing program, Goudarz Molaei, said about 40 percent of the more than 2,600 ticks checked so far this season are carrying the Lyme disease spirochetes. Gregory B. Hladky, courant.com, "Lyme Disease Tick Numbers Now At Record Highs," 25 June 2018 Many other papers have linked HSV-1 with Alzheimer’s and studies have also implicated bacteria as culprits, including pneumonia-causing bacteria and the spirochetes that cause Lyme disease. Melinda Wenner Moyer, Scientific American, "Harder Evidence Builds that Viruses Play a Role in Alzheimer’s," 21 June 2018 The study used multiple methods to evaluate the presence of (Borrelia burgdorferi spirochetes) the bacteria that causes Lyme disease, before and after antibiotic treatment in primates. Maria Clark, NOLA.com, "Lyme disease can persist even after treatment, Tulane study finds," 14 Dec. 2017 The next day, no live spirochetes could be found on the animal’s ulcers, and within three weeks, the ulcers were completely gone. Hadley Leggett, WIRED, "Aug. 31, 1909: First Chemotherapy Drug Treats Syphilis," 31 Aug. 2009 All communicable diseases have window periods during which the infection is so new that the virus, parasite or spirochete can be in the blood and actively replicating, but at such low levels that even the most sensitive tests cannot detect it. Donald G. Mcneil Jr., New York Times, "Orlando Shooting Renews Debate Over Limits on Gay Men Donating Blood," 15 June 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'spirochete.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of spirochete

circa 1877, in the meaning defined above

History and Etymology for spirochete

New Latin Spirochaeta, genus of bacteria, from Latin spira coil + Greek chaitē long hair — more at spire

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The first known use of spirochete was circa 1877

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More Definitions for spirochete


variants: or chiefly British spirochaete \ˈspī-​rə-​ˌkēt \

Medical Definition of spirochete 

: any bacterium of the order Spirochaetales including those causing syphilis and relapsing fever

More from Merriam-Webster on spirochete

Rhyming Dictionary: Words that rhyme with spirochete

Britannica.com: Encyclopedia article about spirochete

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