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Medicine & BodyGreekEnglish

Chlamydia

/kləˈmɪdiə/noun

A genus of bacteria that live inside host cells, and the common sexually transmitted infection they cause.

The Greek roots

χλαμύς
chlamýs
short cloak, mantle

Literally: the cloaked one

Follow a root:χλαμύς1 word

The story of the word

A χλαμύς was a short woollen cloak pinned at the shoulder, standard for cavalrymen and for young Athenian men doing their military service. Halberstädter and von Prowazek, working on trachoma in 1907, saw inclusion bodies that seemed to drape around the host cell nucleus and called the agents Chlamydozoa, cloak animals. The genus name Chlamydia was settled decades later, keeping a garment metaphor for an organism nobody could see properly at the time.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
20th century

Same family

chlamyschlamydospore

In a sentence

Chlamydia is usually silent, which is why screening exists at all.

Trachoma, still a leading cause of preventable blindness, is chlamydia of the eye.

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