spectrum

noun spec·trum \ ˈspek-trəm \

Updated on: 21 May 2018

Definition of spectrum

plural spectra play \ˈspek-trə\ 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

(1) : electromagnetic spectrum

(2) : radio spectrum

(3) : the range of frequencies of sound waves

(4) : mass spectrum

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 spectrum defined for English-language learners

See spectrum defined for kids

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 of spectrum from the Web

Politicians from across the spectrum believe that the government formation will take weeks if not months, given the number of political players, possible combinations of alliances and entrenched interests.

— margaret coker, New York Times, "Iraqi Election Front-Runner Moktada al-Sadr Courts Partners to Govern," 15 May 2018
That would amount to a rotten deal, voices from across the spectrum warned Trump on Monday.

— tory newmyer, Washington Post, "The Finance 202: Trump's China reversal sparks bipartisan fears of a hasty deal," 15 May 2018
Lucky for us, there are so many high-quality oils across the spectrum of snobbery that connoisseurship is purely optional.

— brette warshaw, GQ, "The Best Olive Oils for Any Kitchen," 26 Apr. 2018
Campaign contributions were down overall across the spectrum less than two weeks before the primary, but Democrats still hold a meager sum overall compared to their Republican counterparts.

— seth a. richardson, cleveland.com, "After spending more than $4 million, Mike DeWine still leads the governor's candidates in campaign funds," 26 Apr. 2018
And many people across the spectrum backed stronger border security and crackdowns, such as Operation Gatekeeper, launched in San Diego under President Bill Clinton.

— michael smolens, sandiegouniontribune.com, "Why 'sanctuary' law politics feel different from past immigration flare ups," 22 Apr. 2018
Busch is a master at Bristol, even across a spectrum of weather.

— mike hembree, USA TODAY, "Hembree: Kyle Busch heats up frigid Bristol with second Cup Series win in a row," 16 Apr. 2018
One of the goals is to appeal to people all across the spectrum of interests.

— shawn r. beals, Courant Community, "Connecticut Natives At Wesleyan Organize TEDx Conference," 6 Apr. 2018
Those shot range, in age and race, across the spectrum.

— al saracevic, San Francisco Chronicle, "SF boxer Karim Mayfield facing his biggest fight: for justice," 1 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'spectrum.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of spectrum

New Latin, from Latin, appearance — more at specter

NEW! Time Traveler

First Known Use: 1671

in the meaning defined at sense 1a

See Words from the same year

spectrum Synonyms

Synonyms

gamut, range, scale, spread, stretch;

Related Words

measure, pitch, scale;

ambit, amplitude, compass, dimension(s), extent, reach, realm, scope, sweep, width;

Other Pharmacology Terms

anodyne, cathartic, emetic, emollient, liniment, paregoric, poultice, purgative, soporific

SPECTRUM Defined for English Language Learners

spectrum

noun

Definition of spectrum for English Language Learners

: the group of colors that a ray of light can be separated into including red, orange, yellow, green, blue, indigo, and violet : the colors that can be seen in a rainbow
: an entire range of light waves, radio waves, etc.
: a complete range of different opinions, people, etc.

SPECTRUM Defined for Kids

spectrum

noun spec·trum \ ˈspek-trəm \

Definition of spectrum for Students

plural spectra \-trə\ or spectrums

: the group of different colors including red, orange, yellow, green, blue, indigo, and violet seen when light passes through a prism and falls on a surface or when sunlight is affected by drops of water (as in a rainbow)

Medical Dictionary

spectrum

noun spec·trum \ ˈspek-trəm \

medical Definition of spectrum

plural spectra play \-trə\ 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

(1) : electromagnetic spectrum

(2) : mass spectrum

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