Definition of rotatorian in US English:

rotatorian

noun

Zoology
  • A minute or microscopic animal of the class or phylum Rotatoria; (now) specificallya rotifer.

adjective

Zoology
  • Of or relating to the class or phylum Rotatoria. Now rare.

Origin

Mid 19th century; earliest use found in Andrew Pritchard (1804–1882), microscopist. From Rotatoria + -ian. With use as adjective compare earlier rotatorial.

Pronunciation

rotatorian

/rə(ʊ)təˈtɔːrɪən/