tetrahymena

noun

tet·​ra·​hy·​me·​na ˌte-trə-ˈhī-mə-nə How to pronounce tetrahymena (audio)
: any of a genus (Tetrahymena) of ciliate protozoans

Word History

Etymology

New Latin, from tetra- + Greek hymēn membrane

First Known Use

1962, in the meaning defined above

Time Traveler
The first known use of tetrahymena was in 1962

Rhymes for tetrahymena

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Browse Nearby Words

tetrahydroxy-
tetrahymena
tetraiod-
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Cite this Entry

“Tetrahymena.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tetrahymena. Accessed 8 Jul. 2026.

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Medical Definition

tetrahymena

noun
tet·​ra·​hy·​me·​na -ˈhī-mə-nə How to pronounce tetrahymena (audio)
1
capitalized : a genus of free-living ciliate protozoans much used for genetic and biochemical research
2
: any ciliate protozoan of the genus Tetrahymena
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