spectrum

American  

[spek-truhm] / ˈspɛk trəm /

noun

plural

spectra, spectrums

1. Physics.

   1. an array of entities, as light waves or particles, ordered in accordance with the magnitudes of a common physical property, as wavelength or mass: often the band of colors produced when sunlight is passed through a prism, comprising red, orange, yellow, green, blue, indigo, and violet.

   2. this band or series of colors together with extensions at the ends that are not visible to the eye, but that can be studied by means of photography, heat effects, etc., and that are produced by the dispersion of radiant energy other than ordinary light rays.

2. a broad range of varied but related ideas or objects, the individual features of which tend to overlap so as to form a continuous series or sequence.

   the spectrum of political beliefs.

3. the range of traits and behaviors that are considered to be characteristic of autism spectrum disorder.

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idioms

1. on the spectrum, having an autism spectrum disorder, or displaying behaviors considered characteristic of those disorders.

   The nonprofit works to increase public awareness about the day-to-day issues faced by people on the spectrum.

spectrum British  

/ ˈspɛktrəm /

noun

1. the distribution of colours produced when white light is dispersed by a prism or diffraction grating. There is a continuous change in wavelength from red, the longest wavelength, to violet, the shortest. Seven colours are usually distinguished: violet, indigo, blue, green, yellow, orange, and red

2. the whole range of electromagnetic radiation with respect to its wavelength or frequency

3. any particular distribution of electromagnetic radiation often showing lines or bands characteristic of the substance emitting the radiation or absorbing it See also absorption spectrum emission spectrum

4. any similar distribution or record of the energies, velocities, masses, etc, of atoms, ions, electrons, etc

   a mass spectrum

5. any range or scale, as of capabilities, emotions, or moods

6. another name for an afterimage

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spectrum Scientific  

/ spĕk′trəm /

plural

spectra

1. A range over which some measurable property of a physical phenomenon, such as the frequency of sound or electromagnetic radiation, or the mass of specific kinds of particles, can vary. For example, the spectrum of visible light is the range of electromagnetic radiation with frequencies between between 4.7 × 10 ¹⁴ and 7.5 × 10 ¹⁴ hertz.

2. The observed distribution of a phenomenon across a range of measurement.

3. See more at atomic spectrum spectroscopy

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spectrum Cultural  

1. The range of wavelengths characteristic of a specific type of radiation.

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Discover More

The spectrum making up visible light contains light in the colors violet, indigo, blue, green, yellow, orange, and red, with violet having the shortest wavelength and highest frequency, and red having the longest wavelength and lowest frequency.

Etymology

Origin of spectrum

First recorded in 1605–15; from Latin: “appearance, form,” equivalent to spec(ere) “to look at, regard” + -trum instrumental noun suffix

Example Sentences

Even within France, reactions to her death reflect a spectrum: President Emmanuel Macron called her a “legend of the century,” while others criticized the harm of her rhetoric.

From Salon

There was a rodeo announcer from Idaho, a Kansan whose family owns a dairy farm, and a retired government worker who auctioned spectrum for the Federal Communications Commission.

From The Wall Street Journal

Across the court’s ideological spectrum, there are signs of disagreement about how the court is handling its bulging docket of emergency appeals.

From The Wall Street Journal

KATRIN's exceptionally low background means that nearly all detected electrons originate from tritium decay, allowing for a very clean measurement of the energy spectrum.

From Science Daily

Neither Cook's match nor this one is ideal – they are extreme ends of the spectrum – yet value, significance and history can be attached to both.

From BBC

Related Words

• continuum
• range
• sphere