spectrum

noun

spec·​trum ˈspek-trəm How to pronounce spectrum (audio)
plural spectra ˈspek-trə How to pronounce spectrum (audio) or spectrums
Synonyms of spectrum
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
see also:

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.
Families may also appreciate that the kids’ club has trained autism-spectrum counselors. Chelsea Adams, USA Today, 20 June 2026 Today’s food environment and gaps in health education affect children across the socioeconomic spectrum. Jordan Schriver, The Orlando Sentinel, 19 June 2026 By Friday afternoon, solidarity with Meloni had poured in from across the government and political spectrum, and included a call from President Sergio Mattarella, Italy’s widely respected head of state. ABC News, 19 June 2026 Technology experts from across the political spectrum have contradicted Bezos’ assessment and sounded the alarm about the negative impact AI technology will have on the labor market. Zac Ntim, Deadline, 19 June 2026 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 20 Jun. 2026.

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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