ommatidium

English

Etymology

From the stem form of Ancient Greek ὄμμα (ómma, “eye”).

Pronunciation

• (UK) IPA^(key): /ɒməˈtɪdɪəm/
• (Canada) IPA^(key): /ɑməˈtɪdɪəm/

Noun

ommatidium (plural ommatidia)

1. (zoology) One of the conical substructures which make up the eyes of invertebrates with compound eyes.
   • 1996, Michael J. Roberts, Spiders of Britain and Northern Europe, Collins, published 1996, page 12:

     The ‘compound’ eyes of insects [...] are made up of large numbers of facets or ommatidia, and in this sense, our own eyes are ‘simple’.

Translations

substructure of the eye

• Catalan: ommatidi m
• Finnish: ommatidi (fi)
• French: ommatidie (fr) f
• Spanish: omatidio m

Latin

Pronunciation

• (Classical) IPA^(key): /om.maˈti.di.um/, [ɔmːäˈt̪ɪd̪iʊ̃ˑ]
• (modern Italianate Ecclesiastical) IPA^(key): /om.maˈti.di.um/, [omːäˈt̪iːd̪ium]

Noun

ommatidium n (genitive ommatidiī or ommatidī); second declension

1. ommatidium

Declension

Second-declension noun (neuter).

Case	Singular	Plural
Nominative	ommatidium	ommatidia
Genitive	ommatidiī ommatidī1	ommatidiōrum
Dative	ommatidiō	ommatidiīs
Accusative	ommatidium	ommatidia
Ablative	ommatidiō	ommatidiīs
Vocative	ommatidium	ommatidia

¹Found in older Latin (until the Augustan Age).