thalli (thal-ahy) /ˈθælaɪ/
noun. singular: thallus (thal-uh s) (ˈθæləs)
Botany: A plant body that is not differentiated into stem and leaves and lacks true roots and a vascular system. Thalli are typical of algae, fungi, lichens, and some liverworts.
Derived Forms: thalloid, adjective
Origin: Greek; from thallos green shoot; from thallein to bloom, to sprout