diopter

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di·op·ter

 (dī-ŏp′tər)
n.
A unit of measurement of the refractive power of lenses equal to the reciprocal of the focal length measured in meters.

[Obsolete diopter, an instrument for measuring angles, from Latin dioptra, from Greek dioptrā : dia-, dia- + optos, visible; see okw- in Indo-European roots.]

di·op′tral (-trəl) adj.

di•op•ter

(daɪˈɒp tər)

n.
a unit of measure of the refractive power of a lens, having the dimension of the reciprocal of length and a unit equal to the reciprocal of one meter. Abbr.: D
Also, esp. Brit.,di•op′tre.
[1585–95; < Latin dioptra < Greek: instrument for measuring height or levels =di- di-3 + op- (for ópsesthai to see) + -tra n. suffix of means]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.diopter - a unit of measurement of the refractive power of a lens which is equal to the reciprocal of the focal length measured in meters; used by oculists
unit, unit of measurement - any division of quantity accepted as a standard of measurement or exchange; "the dollar is the United States unit of currency"; "a unit of wheat is a bushel"; "change per unit volume"
Translations
dioptrie

di·op·ter

, dioptre
n. dioptría, unidad de medida de refracción de un lente.

diopter

n dioptría