Definitions for ommatidium
ˌɒm əˈtɪd i əm; -ˈtɪd i əom·ma·tid·i·um

Princeton's WordNetRate this definition:0.0 / 0 votes

1. ommatidiumnoun

   any of the numerous small cone-shaped eyes that make up the compound eyes of some arthropods

WiktionaryRate this definition:0.0 / 0 votes

1. ommatidiumnoun

   One of the conical substructures which make up the eyes of invertebrates.

2. Etymology: From the stem form of ‘eye’ + -idium.

WikipediaRate this definition:0.0 / 0 votes

1. Ommatidium

   The compound eyes of arthropods like insects, crustaceans and millipedes are composed of units called ommatidia (singular: ommatidium). An ommatidium contains a cluster of photoreceptor cells surrounded by support cells and pigment cells. The outer part of the ommatidium is overlaid with a transparent cornea. Each ommatidium is innervated by one axon bundle (usually consisting of 6–9 axons, depending on the number of rhabdomeres): 162  and provides the brain with one picture element. The brain forms an image from these independent picture elements. The number of ommatidia in the eye depends upon the type of arthropod and range from as low as 5 as in the Antarctic isopod Glyptonotus antarcticus, or a handful in the primitive Zygentoma, to around 30,000 in larger Anisoptera dragonflies and some Sphingidae moths.

ChatGPTRate this definition:0.0 / 0 votes

1. ommatidium

   An ommatidium is one of the individual photoreceptive units that make up the compound eye of invertebrates, particularly insects and crustaceans. Each ommatidium consists of a lens, cone, visual cells (or photoreceptor cells), and pigment cells, and contributes to a portion of the overall image perceived by the organism.

WikidataRate this definition:0.0 / 0 votes

1. Ommatidium

   The compound eyes of arthropods like insects, crustaceans and millipedes are composed of units called ommatidia. An ommatidium contains a cluster of photoreceptor cells surrounded by support cells and pigment cells. The outer part of the ommatidium is overlaid with a transparent cornea. Each ommatidium is innervated by one axon and thus provides the brain with one picture element. The brain forms an image from these independent picture elements. The number of ommatidia in the eye depends upon the type of insect and ranges from just a handful in the primitive Archaeognatha and Thysanura to around 30 thousand in larger Anisoptera dragonflies and in some Sphingidae among moths. Ommatidia are typically hexagonal in cross section, and approximately ten times longer than wide. The diameter is largest at the surface, tapering toward the inner end. At the outer surface there is a cornea, below which is a pseudocone which acts to further focus the light. The cornea and pseudocone form the outer 10% of the length of the ommatidium. The inner 90% of the ommatidium contains 6 to 9 in the case of some butterflies long and thin photoreceptor cells often abbreviated "R cells" in literature and often numbered, e.g. R1 through R9. These "R cells" tightly pack the ommatidium. The portion of the R cells at the central axis of the ommatidium collectively form a light guide, a transparent tube, called the rhabdom.

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How to pronounce ommatidium?

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Numerology

1. Chaldean Numerology

   The numerical value of ommatidium in Chaldean Numerology is: 9

2. Pythagorean Numerology

   The numerical value of ommatidium in Pythagorean Numerology is: 1

References

1. ^ Princeton's WordNet
   http://wordnetweb.princeton.edu/perl/webwn?s=ommatidium
2. ^ Wiktionary
   https://en.wiktionary.org/wiki/Ommatidium
3. ^ Wikipedia
   https://en.wikipedia.org/wiki/Ommatidium
4. ^ ChatGPT
   https://chat.openai.com
5. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=ommatidium