ommatidium

noun
om·​ma·​tid·​i·​um | \ ˌä-mə-ˈti-dē-əm How to pronounce ommatidium (audio) \
plural ommatidia\ ˌä-​mə-​ˈti-​dē-​ə How to pronounce ommatidia (audio) \

Definition of ommatidium

: one of the elements corresponding to a small simple eye that make up the compound eye of an arthropod

Keep scrolling for more

Other Words from ommatidium

ommatidial \ ˌä-​mə-​ˈti-​dē-​əl How to pronounce ommatidial (audio) \ adjective

Examples of ommatidium in a Sentence

Recent Examples on the Web

The tiny organ contains 100 ommatidia, or subunits that make up compound eyes found today in many insects, surrounding a light-sensing structure called a rhabdom. Jason Daley, Smithsonian, "Gaze Into a 530-Million-Year-Old Eye, the Oldest Yet Discovered," 11 Dec. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ommatidium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ommatidium

1884, in the meaning defined above

History and Etymology for ommatidium

New Latin, from Greek ommat-, omma eye; akin to Greek ōps eye — more at eye

Keep scrolling for more

Learn More about ommatidium

Dictionary Entries near ommatidium

Ommastrephes

ommateal

ommateum

ommatidium

ommatin

ommatophore

Ommiad

Statistics for ommatidium

Look-up Popularity

Time Traveler for ommatidium

The first known use of ommatidium was in 1884

See more words from the same year

More from Merriam-Webster on ommatidium

Britannica.com: Encyclopedia article about ommatidium

Comments on ommatidium

What made you want to look up ommatidium? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

of or relating to the heavens

Get Word of the Day daily email!

Test Your Vocabulary

Summer 2019 Words of the Day Quiz

  • a-bowl-of-peach-sorbet-with-cut-peaches-next-to-it
  • Which is a synonym of desideratum?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

TAKE THE QUIZ
Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!