chlamydia

American  

[kluh-mid-ee-uh] / kləˈmɪd i ə /

noun

• chlamydiae,
  plural
• chlamydias
  plural

1. Microbiology. any coccoid rickettsia of the genus Chlamydia, parasitic in birds and mammals, including humans, and causing various infections, especially of the eyes, as trachoma, lungs, as psittacosis, and genitourinary tract, as urethritis or chlamydia.

2. Also called lymphogranuloma venereum. Pathology. a widespread, often asymptomatic sexually transmitted disease caused by Chlamydia trachomatis, a major cause of nongonococcal urethritis in men and pelvic inflammatory disease and ectopic pregnancy in women.

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chlamydia British  

/ kləˈmɪdɪə /

noun

1. any Gram-negative bacteria of the genus Chlamydia , which are obligate intracellular parasites and are responsible for such diseases as trachoma, psittacosis, and some sexually transmitted diseases

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chlamydia Scientific  

/ klə-mĭd′ē-ə /

• chlamydiae
  plural

1. Any of various bacteria of the genus Chlamydia, several species of which cause common infections in humans and animals, including neonatal conjunctivitis, pneumonia, bronchitis, pharyngitis, and sexually transmitted infections of the pelvis and urethra.

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Other Word Forms

Noun Inflected Forms

• chlamydiae
  plural
• chlamydias
  plural

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Etymology

Origin of chlamydia

First recorded in 1945 in an article by Helen Jones, Geoffrey Rake, and Barbara Stearns as the proposed name of a taxon; 1966 in the current sense; from New Latin, from Greek chlamyd- (stem of chlamýs chlamys ) + New Latin -ia -ia

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Compare meaning

How does chlamydia compare to similar and commonly confused words? Explore the most common comparisons:

• chlamydia vs. gonorrhea

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Example Sentences

See Examples For:

chlamydia chlamydias

He also raised concerns about a drop in chlamydia testing, which fell by 9% in 2025.

From BBC ● Jun. 2, 2026

And there was: There had been some progress, with oxytetracycline, OTC for short, a powerful antibiotic that is used to treat chlamydia and sometimes syphilis in humans.

From Slate ● Apr. 20, 2026

However, many health departments had already started offering doxy PEP due to the overwhelmingly positive response it showed in clinical trials, reducing chlamydia and gonorrhea by 70% and 50%, respectively.

From Salon ● Jan. 17, 2025

The rates of chlamydia remained about the same in 2023 as the year prior.

From Salon ● Jan. 17, 2025

And so even the lucky koalas like Joe Mangy, who dodge death by chlamydia and return to the wild, still must face off against a myriad of other mortal threats.

From BBC ● Dec. 29, 2024

One branch leads to the domain bacteria, which includes the phyla proteobacteria, chlamydias, spirochetes, cyanobacteria, and Gram-positive bacteria.

From Textbooks ● Jan. 1, 2015

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