/ Dictionary / Index O ocellus: Meaning and Definition of Find definitions for: o•cel•lus Pronunciation: (ō-sel'us), [key] — pl. o•cel•li a type of simple eye common to invertebrates, consisting of retinal cells, pigments, and nerve fibers. an eyelike spot, as on a peacock feather. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: ocellus (Thesaurus) ocellation ocelot Related Content Daily Word Quiz: apogee Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language