thallus

noun

thal·​lus ˈtha-ləs How to pronounce thallus (audio)
plural thalli ˈtha-ˌlī How to pronounce thallus (audio) -ˌlē How to pronounce thallus (audio) or thalluses
: a plantlike vegetative body (as of algae, fungi, or mosses) that lacks differentiation into distinct parts (such as stem, leaves, and roots) and does not grow from an apical point

Word History

Etymology

New Latin, from Greek thallos, from thallein to sprout; akin to Armenian dalar green, fresh, Albanian dal I come forth

First Known Use

1829, in the meaning defined above

Time Traveler
The first known use of thallus was in 1829

Dictionary Entries Near thallus

thallous

thallus

thalposis

See More Nearby Entries 

Cite this Entry

“Thallus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thallus. Accessed 26 Nov. 2024.

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Medical Definition

thallus

noun
thal·​lus ˈthal-əs How to pronounce thallus (audio)
plural thalli ˈthal-ˌī How to pronounce thallus (audio) -ˌē How to pronounce thallus (audio) or thalluses
: a plant or plantlike body (as of an alga, fungus, or moss) that lacks differentiation into distinct members (as stem, leaves, and roots) and does not grow from an apical point

More from Merriam-Webster on thallus

Britannica.com: Encyclopedia article about thallus

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