chla·​myd·​ia | \ klə-ˈmi-dē-ə How to pronounce chlamydia (audio) \
plural chlamydiae\ klə-​ˈmi-​dē-​ˌē How to pronounce chlamydiae (audio) \

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 How to pronounce chlamydial (audio) \ adjective

Examples of chlamydia in a Sentence

Recent Examples on the Web

The Milwaukee area ranked first in gonorrhea rates, fourth in rates of chlamydia and was one of the worst places for HIV for men of color under the age of 25. James Causey, Milwaukee Journal Sentinel, "Taking the HIV medication PrEP is 90% effective. A new drive aims to get more gay black Milwaukee men on it.," 20 June 2019 Nationwide, chlamydia increased 22 percent and gonorrhea increased 67 percent from 2013 to 2017, according to the CDC website. Tess Vrbin,, "No awkward conversations: Department of Public Health promotes confidential notification service, aiming to reduce spread of STDs," 19 June 2019 Doctors will screen for STIs such as gonorrhea and chlamydia even in the absence of symptoms. Sophie Saint Thomas, SELF, "Here’s Why Doctors Don’t Usually Test for Herpes," 10 May 2019 In 2016, there were more than 2 million cases of chlamydia, gonorrhea and syphilis reported to the federal Centers for Disease Control and Prevention. Michelle Andrews, Washington Post, "The ‘Perfect Storm’: Redirecting Family Planning Funds Could Undercut STD Fight," 12 June 2018 Amphora is also in a mid-stage trial for prevention of chlamydia and gonorrhea infections. Evofem, San Diego Union-Tribune, "Evofem gets $80 million for vaginal gel contraceptive," 11 June 2019 Consider getting tested for STIs like chlamydia, syphilis, and gonorrhea. Carolyn Twersky, Seventeen, "Here's What to Do If Your Condom Breaks During Sex," 7 June 2019 Some can be passed from mother to child during pregnancy or childbirth -- notably chlamydia, gonorrhea and syphilis. Nina Avramova, CNN, "One million STDs diagnosed every day, World Health Organization says," 6 June 2019 In 2016, there were an estimated 376.4 million curable cases of chlamydia, gonorrhea, trichomoniasis and syphilis contracted among men and women ages 15 to 49, the WHO reports. Jamie Ducharme, Time, "A Million New STIs Are Contracted Every Day, the WHO Says," 7 June 2019

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

10 Aug 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 How to pronounce chlamydia (audio) \

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 How to pronounce chlamydiae (audio) \ 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 How to pronounce chlamydial (audio) \ adjective

More from Merriam-Webster on chlamydia

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

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