electromagnetic spectrum

American  

noun

1. the entire spectrum, considered as a continuum, of all kinds of electric, magnetic, and visible radiation, from gamma rays having a wavelength of 0.001 angstrom to long waves having a wavelength of more than 1 million km.

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electromagnetic spectrum British  

noun

1. the complete range of electromagnetic radiation from the longest radio waves (wavelength 10 ⁵ metres) to the shortest gamma radiation (wavelength 10 ^–13 metre)

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electromagnetic spectrum Scientific  

1. The entire range of electromagnetic radiation. At one end of the spectrum are gamma rays, which have the shortest wavelengths and high frequencies. At the other end are radio waves, which have the longest wavelengths and low frequencies. Visible light is near the center of the spectrum.

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electromagnetic spectrum Cultural  

1. The family of electromagnetic waves. The electromagnetic spectrum, starting from the waves with the longest wavelengths (and least energy), consists of radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays, and gamma radiation. Members of the family differ from one another only in their wavelength, or frequency. For example, the wavelength of blue light is roughly half that of red light, but the waves corresponding to the two colors are otherwise identical.

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Etymology

Origin of electromagnetic spectrum

First recorded in 1935–40

Example Sentences

Detecting light and radiation is essential across the electromagnetic spectrum, but some regions remain especially challenging.

From Science Daily • May 31, 2026

The aircraft use advanced sensors to "intercept and analyse signals across the electromagnetic spectrum, providing real-time strategic and tactical intelligence", according to the RAF website.

From BBC • May 20, 2026

Looking up and dealing with “first contact” from the sky or the electromagnetic spectrum is the new reality, said Bartholomees.

From The Wall Street Journal • Dec. 13, 2025

The quasars eat way too much that all of the dust and gas falling into the black hole becomes super hot and begins to glow bright, emitting light across the electromagnetic spectrum.

From Space Scoop • Mar. 27, 2025

Moreover, radio represents a large fraction of the electromagnetic spectrum.

From "Cosmos" by Carl Sagan