vorticella, n. [NL., dim. fr. L. vortex. See Vortex.].
Any one of numerous species of ciliated Infusoria belonging to Vorticella and many other genera of the family Vorticellidæ. They have a more or less bell-shaped body with a circle of vibrating cilia around the oral disk. Most of the species have slender, contractile stems, either simple or branched. [1913 Webster]