Word Study
thallus
CIDE DICTIONARY
thallus, n. [NL., fr. Gr. young shoot or branch, frond.].
A solid mass of cellular tissue, consisting of one or more layers, usually in the form of a flat stratum or expansion, but sometimes erect or pendulous, and elongated and branching, and forming the substance of the thallogens. [1913 Webster]
OXFORD DICTIONARY
thallus, n. (pl. thalli) a plant-body without vascular tissue and not differentiated into root, stem, and leaves.
Derivative
thalloid adj.
Etymology
L f. Gk thallos green shoot f. thallo bloom
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