Definition of thallus
plural thalli play \ˈtha-ˌlī, -ˌlē\ or thalluses
: a plant body that lacks differentiation into distinct parts (as stem, leaves, and roots), does not grow from an apical point, and is characteristic of organisms formerly classified as thallophytes
Origin of thallus
New Latin, from Greek thallos, from thallein to sprout; akin to Armenian dalar green, fresh, Albanian dal I come forth
First Known Use: 1829
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