thallus

noun
thal·​lus | \ ˈtha-ləs How to pronounce thallus (audio) \
plural thalli\ ˈtha-​ˌlī How to pronounce thallus (audio) , -​ˌlē \ or thalluses

Definition of thallus

: 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

First Known Use of thallus

1829, in the meaning defined above

History and Etymology for thallus

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

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The first known use of thallus was in 1829

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Cite this Entry

“Thallus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thallus. Accessed 17 Jun. 2021.

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More Definitions for thallus

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

Medical Definition of thallus

: 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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