- one of the radial elements composing a compound eye.
Origin of ommatidium
1880–85; < New Latin < Greek ommat- (stem of ómma eye) + New Latin -idium -idium
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for ommatidium
Ommatidium -ia: one of the elements of which the compound eye is composed.Explanation of Terms Used in Entomology
John. B. Smith
The ommatidium is from the first segregate and consists of few cells.
The cells of the ommatidium are a good deal larger than the neighbouring common cells of the epidermis.
The ommatidium (soft structure beneath the lens-unit of a compound eye) is very simple in both Scorpio and Limulus.
Each of these facets is the external window of an eye element or ommatidium.Elementary Zoology, Second Edition
Vernon L. Kellogg
- any of the numerous cone-shaped units that make up the compound eyes of some arthropods
C19: via New Latin from Greek ommatidion, from omma eye
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- 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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.