Breadcrumb Home > Thesaurus > O Synonyms of ommatidium Find synonyms for: Noun1. ommatidium, simple eye, stemma, ocellususage: any of the numerous small cone-shaped eyes that make up the compound eyes of some arthropodsWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of ommatidium (Dictionary) ✖ Related Content Daily Word Quiz: unctuous Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language