Word.ws English Dictionary

diopter

diopter noun: 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.

Noun

diopter (plural diopters)

  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. The dioptre adjustment mechanism of a pair of binoculars or of a camera viewfinder.
  3. (dated) A lens element attached to the front of a photographic lens to shorten the lens's minimum focus distance; also called a "close-up filter".
  4. (obsolete) Any lens system, such as a telescope.
  5. (obsolete) A theodolite or similar surveyor’s angle measuring device.
  6. (obsolete) An alidade.
  7. (obsolete) A surgical speculum.
  8. (obsolete) An instrument for drawing the skull by projections.

diopter meaning in Tamil

diopter in Tamil

டையாப்ட்டர், தையொத்தர்

Forms of diopter

pluraldiopters
alternative formdioptra
alternative formdioptre
alternative formdioptry

Origin of diopter

From Latin dioptra, from Ancient Greek διόπτρα (dióptra).

Questions about diopter

What does diopter mean?
Diopter means 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.
What is diopter in Tamil?
Diopter in Tamil is டையாப்ட்டர், தையொத்தர். See Diopter meaning in Tamil.
What part of speech is diopter?
Diopter is a noun.
What is the plural of diopter?
The plural of diopter is diopters.

Words near diopter in the dictionary

  1. diopsidite
  2. diopsidites
  3. diopsids
  4. dioptase
  5. dioptases
  6. diopter
  7. diopteric aberration
  8. diopteric aberrations
  9. diopters
  10. dioptid
  11. dioptids

Source and license

Adapted from Wiktionary: diopter (page history and authors); diopter (Tamil Wiktionary) (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Vealhurl-diopter.wav.

Cite this entry: “diopter.” Word.ws, https://word.ws/diopter. Based on Wiktionary, CC BY-SA 4.0.