Word Pronunciation & Dictionary

diopter

Word Rarity Very rare

Frequency: 1.79 in modern English

Syllables: diopter
IPA

10

Scrabble Score

7

Letters

1

Syllables

7

Unique Chars

Meaning

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

The dioptre adjustment mechanism of a pair of binoculars or of a camera viewfinder.

noun

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".

Dated

noun

Any lens system, such as a telescope.

Obsolete

noun

A theodolite or similar surveyor’s angle measuring device.

Obsolete

noun

Obsolete

noun

A surgical speculum.

Obsolete

noun

An instrument for drawing the skull by projections.

Obsolete

Etymology

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

Origin

Source language: Latin

Word Breakdown

Root: dioptra, διόπτρα

Usage

Inflected Forms

diopters (plural) dioptra (alternative) dioptre (alternative) dioptry (alternative)

Synonyms

dioptre

Questions

What does diopter mean?: 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.
Where does diopter come from?: It is traced to Latin.

How to pronounce diopter

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