spi·​ro·​chete | \ ˈspī-rə-ˌkēt How to pronounce spirochete (audio) \
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

Recent Examples on the Web Through this method, India became yaws-free in 2016, though the emergence of antibiotic resistance in the spirochete may complicate efforts. Quanta Magazine, "How to Permanently End Diseases," 3 Dec. 2019 Acute encephalitis syndrome, including Japanese encephalitis, is caused by several different viruses, bacteria, fungi, parasites, spirochetes, chemical and toxins. Washington Post, "India’s worst-hit state for encephalitis turning a tide," 2 Nov. 2019 Barbour had spent the year learning the complex requirements for growing Borrelia, a type of spirochete transmitted by ticks or lice. Allen Steere, BostonGlobe.com, "Lyme disease: How we discovered it and where we go from here," 22 Aug. 2019 In 1982, while dissecting the mid-gut of a tiny nymphal Ixodes scapularis tick, Burgdorfer noted what looked like spirochetes. Allen Steere, BostonGlobe.com, "Lyme disease: How we discovered it and where we go from here," 22 Aug. 2019 Ibsen’s ghosts were not just spirochetes but also ideas: the false ones that ruin lives and generations. Jesse Green, New York Times, "On Adjacent Stages, Two Haunted Houses, Circa 1882 and 2019," 12 Aug. 2019 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

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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Time Traveler

The first known use of spirochete was circa 1877

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Cite this Entry

“Spirochete.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spirochete. Accessed 30 Nov. 2020.

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More Definitions for spirochete


variants: or chiefly British spirochaete \ ˈspī-​rə-​ˌkēt How to pronounce spirochaete (audio) \

Medical Definition of spirochete

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

More from Merriam-Webster on spirochete

Britannica.com: Encyclopedia article about spirochete

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