Pronunciation: (u-kan'thus),[key] —n., —pl.-thus•es, -thiPronunciation: (-thī).[key] 1. any of several plants of the genus Acanthus, of the Mediterranean region, having spiny or toothed leaves and showy, white or purplish flowers. Cf. acanthus family. 2. an architectural ornament, as in the Corinthian capital, resembling the leaves of this plant.