noun, plural om·ma·tid·i·a [om-uh–tid-ee-uh] /ˌɒm əˈtɪd i ə/. Zoology.
- one of the radial elements composing a compound eye.
noun plural -tidia (-ˈtɪdɪə)
- any of the numerous cone-shaped units that make up the compound eyes of some arthropods
- One of the tiny light-sensitive parts of the compound eye of insects and other arthropods. An ommatidium resembles a single simplified eye. See more at compound eye.