thallus

[ thal-uhs ]

noun

, Botany, Mycology.

, plural thal·li [thal, -ahy], thal·lus·es.

1. a simple vegetative body undifferentiated into true leaves, stem, and root, ranging from an aggregation of filaments to a complex plantlike form.

thallus

/ ˈθæləs /

noun

1. the undifferentiated vegetative body of algae, fungi, and lichens

thallus

/ thăl′əs /

, Plural thalli thăl′ī

1. A type of body found among plants and fungi that is not differentiated into roots, stems, or leaves. Thalli are found among lichens, mosses, liverworts, and many algae, as well as the gametophyte generations of horsetails and ferns, which have rhizoids but not true roots.

Derived Forms

• ˈthalloid, adjective

Word History and Origins

Origin of thallus¹

1820–30; < New Latin < Greek thallós young shoot, twig

Word History and Origins

Origin of thallus¹

C19: from Latin, from Greek thallos green shoot, from thallein to bloom

Example Sentences

In these there is a thallus which starts from a central point and continually divides in a forked or dichotomous manner.

From Project Gutenberg

The plant-body of a sea weed is called a thallus, and differs considerably in the various species.

From Project Gutenberg

Another method is by the agency of little spores (zoospores) that are produced at the edges or extremities of the thallus.

From Project Gutenberg

They are many times forked in the same plane, which produces a flat thallus.

From Project Gutenberg

The structure of the thallus may serve to represent that of most of the Lichens.

From Project Gutenberg