Diopter

Alternative forms

• dioptra
• dioptre

Origin

From French dioptre, from Latin dioptra, from Greek διοπτρα ("to see through").

Oxford Dictionaries

Full definition of diopter

Noun

1. A unit of measure of the power of a lens or mirror, equal to the reciprocal of its focal length in meters. Myopia is diagnosed and measured in diopters.
2. (obsolete) Any lens system, such as a telescope.
3. (obsolete) A theodolite or similar surveyor’s angle measuring device.
4. (obsolete) An alidade.
5. (obsolete) A surgical speculum.
6. (obsolete) An instrument for drawing the skull by projections.

Anagrams

• dioptre
• peridot
• proetid
• proteid
• protide