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n. Physics The distribution of a characteristic of a physical system or phenomenon, especially:

n. Physics The distribution of energy emitted by a radiant source, as by an incandescent body, arranged in order of wavelengths.

n. Physics The distribution of atomic or subatomic particles in a system, as in a magnetically resolved molecular beam, arranged in order of masses.

n. A graphic or photographic representation of such a distribution.

n. A range of values of a quantity or set of related quantities.

n. A broad sequence or range of related qualities, ideas, or activities: the whole spectrum of 20th-century thought.

n. A range; a continuous, infinite, one-dimensional set, possibly bounded by extremes.

n. The pattern of absorption or emission of radiation produced by a substance when subjected to energy (radiation, heat, electricity, etc.).

n. The set of eigenvalues of a matrix.

n. Of a bounded linear operator A, the set of scalar values λ such that the operator A—λI, where I denotes the identity operator, does not have a bounded inverse; intended as a generalisation of the linear algebra sense.

n. An apparition; a specter.

n.

n. 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.

n. 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.

n. A specter; a ghostly phantom.

n. An image of something seen, continuing after the eyes are closed, covered, or turned away.

n. In physics, the continuous band of light (visible spectrum) showing the successive prismatic colors, or the isolated lines or bands of color, observed when the radiation from such a source as the sun, or an ignited vapor in a gas-flame, is viewed after having been passed through a prism (prismatic spectrum) or reflected from a diffraction-grating (diffraction- or interference-spectrum).

n. In zoology, a generic name variously used:

n. A genus of lepidopterous insects.

n. A genus of gressorial orthopterous insects: same as

n. A genus of lemuroid mammals: same as

n. The specific name of some animals, including Tarsius spectrum and Phyllostoma spectrum.

n. That portion, of any spectrum, which consists of rays less refrangible than the longest wave-lengths of the visible spectrum.

n. an ordered array of the components of an emission or wave

n. a broad range of related objects or values or qualities or ideas or activities

"The Supreme Court has distinguished the regulation of radio spectrum from the regulation of printing presses, and applied more lenient scrutiny to the regulation of spectrum, based on its conclusion that the spectrum is unusually scarce."

reach    scope    range    compass    orbit    ambit   

comparison spectrum    gitter-spectrum    atmospheric spectrum    prismatic spectrum    spectrum of the second order    fluted spectrum    metallic spectra    secondary spectrum    infra-red spectrum    emission-spectrum   

spectral   

spectra    light    spectroscope    ocular spectrum   

light spectrum   

apparition    specter   

frequency    measurement    radiation    component    emission    range    detector    wavelength    output    density