Pronunciation: (thal'us), [key]
—pl. thal•liPronunciation: (thal'ī), [key] thal•lus•es. Bot., Mycol.
a simple vegetative body undifferentiated into true leaves, stem, and root, ranging from an aggregation of filaments to a complex plantlike form.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.