Word Study
ommatidium
CIDE DICTIONARY
ommatidium, n. [NL., dim. of Gr. , , the eye.].
One of the single eyes forming the compound eyes of crustaceans, insects, and other invertebrates; one of the eyes of an ommateum . [1913 Webster]
OXFORD DICTIONARY
ommatidium, n. (pl. ommatidia) a structural element in the compound eye of an insect.
Etymology
mod.L f. Gk ommatidion dimin. of omma ommat- eye
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