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• angstrom
  angstrom

  noun

  a unit of length, equal to one tenth of a millimicron, or one ten millionth of a millimeter, primarily used to express electromagnetic wavelengths. Å; A
• Ångström
  Ångström

  noun

  Anders Jonas 1814–74, Swedish astronomer and physicist.

angstrom

¹ American  

[ang-struhm] / ˈæŋ strəm /

noun

(often initial capital letter)

1. a unit of length, equal to one tenth of a millimicron, or one ten millionth of a millimeter, primarily used to express electromagnetic wavelengths. Å; A

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Ångström ² American  

[ang-struhm, awng-strœm] / ˈæŋ strəm, ˈɔŋ strœm /

noun

1. Anders Jonas 1814–74, Swedish astronomer and physicist.

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Ångström ¹ British  

/ ˈæŋstrəm, ˈɔŋstrœm /

noun

1. Anders Jonas (ˈandərs ˈjuːnas). 1814–74, Swedish physicist, noted for his work on spectroscopy and solar physics

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angstrom ² British  

/ ˈæŋstrʌm, -strəm /

noun

1.  Å.   A.  Also called: angstrom unit.  a unit of length equal to 10 ^–10 metre, used principally to express the wavelengths of electromagnetic radiations. It is equivalent to 0.1 nanometre

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Ångström ¹ Scientific  

/ ăng′strəm /

1. Swedish physicist and astronomer who pioneered the use of the spectroscope in the analysis of radiation. By studying the spectrum of visible light given off by the Sun, Ångström discovered that there is hydrogen in the Sun's atmosphere. The angstrom unit of measurement is named for him.

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angstrom ² Scientific  

/ ăng′strəm /

1. A unit of length equal to one hundred-millionth (10 ^{- 10}) of a meter. It was once used to measure wavelengths of light and the diameters of atoms, but has now been mostly replaced by the nanometer.

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Etymology

Origin of angstrom

First recorded in 1895–1900; named after A. J. Ångström ( def. )

Example Sentences

See Examples For:

angstrom Ångström

The channels are built from proteins and contain extremely narrow regions at the angstrom scale.

From Science Daily ● Feb. 19, 2026

Note: The length unit angstrom, Å, is often used to represent atomic-scale dimensions and is equivalent to 10−10 m.

From Textbooks ● Feb. 14, 2019

An angstrom is the unit commonly used for the expression of atomic-scale dimensions.

From Textbooks ● Jan. 1, 2015

Use your normal speaking voice—don't speak slowly or strain to over-pronounce "angstrom."

From Slate ● Apr. 6, 2011

The visible spectrum ranges from 8,000 to 4,000 angstrom units.*

From Time Magazine Archive

This technique can be used to improve the resolution of fluorescence microscopy down to the Ångström scale -- far below the classical diffraction limit of light.

From Science Daily ● Apr. 24, 2024

The discovery that hydrogen exists in the atmosphere of the sun was made by Ångström in 1862.

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Agnes M. (Agnes Mary) Clerke

A. J. Ångström of Upsala takes rank after Kirchhoff as a subordinate founder, so to speak, of solar spectroscopy.

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Agnes M. (Agnes Mary) Clerke

The man who, in a published paper, came nearest to the philosophy of the subject was Ångström.

From Six Lectures on Light Delivered In The United States In 1872-1873 by John Tyndall

In point of fact, Ångström was still, in 1853, divided between adsorption and interference as the mode of origin of the Fraunhofer dark rays.

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Agnes M. (Agnes Mary) Clerke