ommatidium

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Related to ommatidia: Rhabdomere

om·ma·tid·i·um

 (ŏm′ə-tĭd′ē-əm)
n. pl. om·ma·tid·i·a (-ē-ə)
One of the optical units, consisting of photoreceptors and usually one or more lenses, that make up a compound eye of an insect or a crustacean.

[New Latin, diminutive of Greek omma, ommat-, eye; see okw- in Indo-European roots.]

om′ma·tid′i·al (-ē-əl) adj.

ommatidium

(ˌɒməˈtɪdɪəm)
n, pl -tidia (-ˈtɪdɪə)
(Zoology) 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]
ˌommaˈtidial adj

om•ma•tid•i•um

(ˌɒm əˈtɪd i əm)

n., pl. -tid•i•a (-ˈtɪd i ə)
one of the units that make up the compound eye of insects and other arthropods.
[1880–85; < New Latin < Greek ommat-]
om`ma•tid′i•al, adj.

om·ma·tid·i·um

(ŏm′ə-tĭd′ē-əm)
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.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.ommatidium - any of the numerous small cone-shaped eyes that make up the compound eyes of some arthropods
ocellus, simple eye, stemma - an eye having a single lens
compound eye - in insects and some crustaceans: composed of many light-sensitive elements each forming a portion of an image
References in periodicals archive ?
They found the ancient creature had a primitive form of compound eye - an optical organ that consists of arrays of tiny visual cells, called ommatidia, similar to those of present-day bees.
In an adult animal, each LE contains more than a thousand ommatidia consisting of a conical lens below which are located 5-12 photoreceptors, also called retinular cells, arranged like the sections of an orange.
What makes a mantis shrimp's eye so powerful is that it's comprised of thousands of light-trapping facets called ommatidia that are each divided into three sections that can move independently.
The front of male wider than the 1st flagellomere, and ommatidia uniform in size (fig.
Additionally, development of the ommatidia gave the eye a visibly granular texture and caused a halo effect around the eye.
Eyes bare, broadly abutting medially, shorter than length of 1 ommatidia.
And the scene in each of the tiny ommatidia (radial units composing compound eyes) that compose every compound eye is completely different with each passing instant.
While you and I, and most other animals on Earth, are equipped with just a pair of standard eyes (simple eyes in biological parlance), some living creatures have compound eyes that are made of thousands of ommatidia.
The researchers developed new ideas in materials and fabrication strategies allowing construction of artificial ommatidia in large, interconnected arrays in hemispherical layouts.
For this~ we wil analyze the effect of loss of function of these genes in the adult eye and in the wing, to check whether we can detect a disruption of the regular arrangement of ommatidia or bristles in the mutant tissue.
7); eye bare, ommatidia homogeneous in size; setae on head strong, black, except finer and white on gena, palpus and proboscis.
The most common lesions observed in histology were idiopathic blindness arising from the loss of ommatidia in the eyes, followed by the presence of nonspecific, or idiopathic, granulomas in a variety of tissues.