The several colored and other rays of which light is composed, separated by the refraction of a prism or other means, and observed or studied either as spread out on a screen, by direct vision, by photography, or otherwise. See Illust. of Light, and Spectroscope.
A luminous appearance, or an image seen after the eye has been exposed to an intense light or a strongly illuminated object. When the object is colored, the image appears of the complementary color, as a green image seen after viewing a red wafer lying on white paper. Called also ocular spectrum.
Red is such an interesting color to correlate with emotion, because it's on both ends of the spectrum. On one end you have happiness, falling in love, infatuation with someone, passion, all that. On the other end, you've got obsession, jealousy, danger, fear, anger and frustration. Taylor Swift
The past, like the future, is indefinite and exists only as a spectrum of possibilities. Stephen Hawking
Mild autism can give you a genius like Einstein. If you have severe autism, you could remain nonverbal. You don't want people to be on the severe end of the spectrum. But if you got rid of all the autism genetics, you wouldn't have science or art. All you would have is a bunch of social 'yak yaks.' Temple Grandin
A wingnut is someone on the far-right wing or far-left wing of the political spectrum - the professional partisans, the unhinged activists and the paranoid conspiracy theorists. They're the people who always try to divide rather than unite us. John Avlon
Einstein's theory of relativity does a fantastic job for explaining big things. Quantum mechanics is fantastic for the other end of the spectrum - for small things. Brian Greene