chla·​myd·​ia | \ klə-ˈmi-dē-ə \
plural chlamydiae\ klə-​ˈmi-​dē-​ˌē \

Definition of chlamydia

1 : any of a genus (Chlamydia, family Chlamydiaceae) of spherical gram-negative intracellular bacteria especially : one (C. trachomatis) that causes or is associated with various diseases of the eye and urogenital tract including trachoma, lymphogranuloma venereum, cervicitis, and some forms of urethritis
2 : a disease or infection caused by chlamydiae

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Other Words from chlamydia

chlamydial \ klə-​ˈmi-​dē-​əl \ adjective

Examples of chlamydia in a Sentence

Recent Examples on the Web

In particular, the symptoms or M. genitalium are similar to those of chlamydia. Claire Gillespie, SELF, "The FDA Just Approved the First Test for Mycoplasma Genitalium, a Commonly Misdiagnosed STI," 1 Feb. 2019 While primary and secondary syphilis diagnoses went up by 76 percent, chlamydia remained the most commonly reported to the CDC with nearly half of the new cases occurring in females ages 15-to-24. Alexandria Hein, Fox News, "STDs hit all-time highs in US for fourth straight year, CDC reports," 28 Aug. 2018 Gonorrhea, chlamydia, and syphilis are all curable and HIV can be prevented by taking daily PrEP. SELF, "Here's Why Sexually Transmitted Infection Rates Are So High, According to STI Experts," 8 Jan. 2019 The investigation also reported that in 2017, 420,000 STDs were diagnosed in England, with chlamydia accounting for 48 percent of cases. Alexandria Hein, Fox News, "'Flesh-eating' STD allegedly reported in England," 22 Aug. 2018 Women who are diagnosed with chlamydia and whose symptoms don’t go away with standard antibiotic treatment may want to ask their doctors about other causes for their symptoms, Manhart adds. Amanda Macmillan,, "What Is Mycoplasma Genitalium? British Doctors Are Warning That This Sexually Transmitted Infection Could Be the Next Big Superbug," 11 July 2018 Those 12 men then took a cocktail of different antibiotics used for a range of conditions from drug-resistant bacterial meningitis to chlamydia. Cathleen O'grady, Ars Technica, "Gut bacteria recover from antibiotics, but they may take six months," 28 Oct. 2018 Furthermore, women are less likely than men to show symptoms with common STIs, like chlamydia and gonorrhea, and thus, may not seek out the necessary care and treatment. Lauren Valenti, Vogue, "STD Rates Have Hit an All-Time High in the U.S.—And Here’s Why," 29 Aug. 2018 There are a bunch of STIs condoms can help protect you against, including HIV, gonorrhea, trichomoniasis, and chlamydia, according to the Centers for Disease Control and Prevention (CDC). Korin Miller, SELF, "These Are the Only Kinds of Birth Control That Also Protect Against STIs," 27 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'chlamydia.' 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 chlamydia

1966, in the meaning defined at sense 1

History and Etymology for chlamydia

New Latin, from Greek chlamyd-, chlamys

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Last Updated

9 Feb 2019

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The first known use of chlamydia was in 1966

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chla·​myd·​ia | \ klə-ˈmid-ē-ə \

Medical Definition of chlamydia

1 capitalized : the type genus of the family Chlamydiaceae comprising coccoid to spherical gram-negative intracellular parasitic bacteria and including one (C. trachomatis) that causes or is associated with various diseases of the eye and genitourinary tract including trachoma, lymphogranuloma venereum, cervicitis, and some forms of nongonococcal urethritis

2 plural chlamydiae\ -​ē-​ˌē, -​ˌī \ also chlamydias

a : a bacterium of the genus Chlamydia
b : an infection or disease caused by a bacterium of the genus Chlamydia

Other Words from chlamydia

chlamydial \ -​ē-​əl \ adjective

More from Merriam-Webster on chlamydia

Rhyming Dictionary: Words that rhyme with chlamydia Encyclopedia article about chlamydia

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