dioptrate

adjective

di·​op·​trate

dīˈäpˌtrāt,

-trə̇t

: divided by a transverse line or septum

—used of the compound eyes of certain insects (such as water beetles) and of ocelli on the wings of certain moths and butterflies

Word History

Etymology

dia- + optr- (irregular from Greek opsesthai to be going to see) + -ate

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