spectrum

noun

spec·​trum ˈspek-trəm How to pronounce spectrum (audio)
plural spectra ˈspek-trə How to pronounce spectrum (audio) or spectrums
1
a
: a continuum of color formed when a beam of white light is dispersed (as by passage through a prism) so that its component wavelengths are arranged in order
b
: any of various continua that resemble a color spectrum in consisting of an ordered arrangement by a particular characteristic (such as frequency or energy): such as
(3)
: the range of frequencies of sound waves
c
: the representation (such as a plot) of a spectrum
2
a
: a continuous sequence or range
a wide spectrum of interests
opposite ends of the political spectrum
b
: kinds of organisms associated with a particular situation (such as an environment)
c
: a range of effectiveness against pathogenic organisms
an antibiotic with a broad spectrum
Phrases
on the spectrum
: exhibiting traits associated with autism spectrum disorder
… quiet areas and sensory bags with headphones … and other ways to help kids who are on the spectrum cope with unfamiliar, noisy surroundings.Rachel Molenda
… Stephanie Adams, cofounder of the Autism and Asperger's Society, said: "We started the society because we wanted to make a place where people on the spectrum can spend their time and not feel isolated. …"Kelsey Maxwell

Examples of spectrum in a Sentence

beautiful scarves in all the colors of the spectrum the complete spectrum of opinions on this hotly debated subject
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Even the lower end of that spectrum is considerably larger than the most lucrative contract the Cubs have dished out in team history (Jason Heyward $184 million). Zach Pressnell, MSNBC Newsweek, 16 Aug. 2025 Over the week of campaign stops, a range of officials from across the Democratic political spectrum voiced their support for the candidate. Josephine Stratman, New York Daily News, 15 Aug. 2025 Find a huge range of styles for your reading glasses on Amazon, from classic to trendy, and a wide spectrum of magnifications. Nora Colomer May Earn A Commission If You Buy Through Our Referral Links. This Content Was Created By A Team That Works Independently From The Fox Newsroom., FOXNews.com, 14 Aug. 2025 Read More: What an HPV Diagnosis Really Means It’s been interesting to see the spectrum of reactions play out, Van Hoose says. Angela Haupt, Time, 14 Aug. 2025 See All Example Sentences for spectrum

Word History

Etymology

New Latin, from Latin, appearance — more at specter

First Known Use

1672, in the meaning defined at sense 1a

Time Traveler
The first known use of spectrum was in 1672

Browse Nearby Words

Cite this Entry

“Spectrum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spectrum. Accessed 27 Aug. 2025.

Kids Definition

spectrum

noun
spec·​trum ˈspek-trəm How to pronounce spectrum (audio)
plural spectra -trə How to pronounce spectrum (audio) or spectrums
1
a
: the group of different colors including red, orange, yellow, green, blue, indigo, and violet arranged in the order of their wavelengths and seen when white light passes through a prism and falls on a surface or when sunlight is scattered by water droplets to form a rainbow
2
: a continuous range or series
a wide spectrum of interests

Medical Definition

spectrum

noun
spec·​trum ˈspek-trəm How to pronounce spectrum (audio)
plural spectra -trə How to pronounce spectrum (audio) or spectrums
1
a
: a continuum of color formed when a beam of white light is dispersed (as by passage through a prism) so that its component wavelengths are arranged in order
b
: any of various continua that resemble a spectrum in consisting of an ordered arrangement by a particular characteristic (as frequency or energy): as
c
: the representation (as a plot) of a spectrum
2
: a continuous sequence or range
specifically : a range of effectiveness against pathogenic organisms see broad-spectrum, narrow-spectrum

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