Try Our Apps


World Series Quiz


[om-uh-tid-ee-uh m] /ˌɒm əˈtɪd i əm/
noun, plural ommatidia
[om-uh-tid-ee-uh] /ˌɒm əˈtɪd i ə/ (Show IPA).
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
Related forms
ommatidial, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2016.
Cite This Source
Examples from the Web for ommatidia
Historical Examples
British Dictionary definitions for ommatidia


noun (pl) -tidia (-ˈtɪdɪə)
any of the numerous cone-shaped units that make up the compound eyes of some arthropods
Derived Forms
ommatidial, adjective
Word Origin
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
Cite This Source
ommatidia in Science
Plural ommatidia
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 © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source

Word of the Day

Difficulty index for ommatidium

Few English speakers likely know this word

Word Value for ommatidia

Scrabble Words With Friends

Nearby words for ommatidia