prothallium

noun

pro·​thal·​li·​um prō-ˈtha-lē-əm How to pronounce prothallium (audio)
plural prothallia prō-ˈtha-lē-ə How to pronounce prothallium (audio)
: prothallus

Word History

Etymology

New Latin, from pro- + thallus

First Known Use

1858, in the meaning defined above

Time Traveler
The first known use of prothallium was in 1858

Rhymes for prothallium

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Browse Nearby Words

prothallic
prothallium
prothalloid
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Cite this Entry

“Prothallium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/prothallium. Accessed 7 Jul. 2026.

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More from Merriam-Webster on prothallium

Britannica.com: Encyclopedia article about prothallium

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