dispersion

American  

[dih-spur-zhuhn, -shuhn] / dɪˈspɜr ʒən, -ʃən /

noun

1. Also an act, state, or instance of dispersing or of being dispersed.

2. Optics.

   1. the variation of the index of refraction of a transparent substance, as glass, with the wavelength of light, with the index of refraction increasing as the wavelength decreases.

   2. the separation of white or compound light into its respective colors, as in the formation of a spectrum by a prism.

3. Statistics. the scattering of values of a variable around the mean or median of a distribution.

4. Military. a scattered pattern of hits of bombs dropped under identical conditions or of shots fired from the same gun with the same firing data.

5. Also called disperse system.  Physical Chemistry. a system of dispersed particles suspended in a solid, liquid, or gas.

6. (initial capital letter) Diaspora.

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Dispersion ¹ British  

/ dɪˈspɜːʃən /

noun

1. another name for the Diaspora

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dispersion ² British  

/ dɪˈspɜːʃən /

noun

1. another word for dispersal

2. physics

   1. the separation of electromagnetic radiation into constituents of different wavelengths

   2.  D.  a measure of the ability of a substance to separate by refraction, expressed by the first differential of the refractive index with respect to wavelength at a given value of wavelength

3. statistics the degree to which values of a frequency distribution are scattered around some central point, usually the arithmetic mean or median

4. chem a system containing particles dispersed in a solid, liquid, or gas

5. military the pattern of fire from a weapon system

6. 1. the range of speeds of such objects as the stars in a galaxy

   2. the frequency-dependent retardation of radio waves as they pass through the interstellar medium

   3. the deviation of a rocket from its prescribed path

7. ecology the distribution pattern of an animal or a plant population

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dispersion Scientific  

/ dĭ-spûr′zhən /

1. The separation by refraction of light or other radiation into individual components of different wavelengths. Dispersion results in most materials because a material's index of refraction depends on the wavelength of the radiation passing through it; thus different wavelengths entering a material along the same path will fan out into different paths within it. Prisms, for example, diffuse white light (which contains an even mixture of visible wavelengths) into its variously colored components; rainbows are an effect of dispersion in water droplets.

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Other Word Forms

• nondispersion noun
• predispersion noun

Etymology

Origin of dispersion

1350–1400; Middle English dispersio ( u ) n (< Anglo-French ) < Latin dispersiōn- (stem of dispersiō ), equivalent to dispers ( us ) ( see disperse) + -iōn- -ion

Explanation

The noun dispersion means the process of distributing something over an area. A combination of your yearly planting of new bulbs and their natural tendency to spread has led to the dispersion of daffodils over your entire back yard. Dispersion refers to the act of spreading something, like your dispersion of sprinkles evenly over three dozen cupcakes. It can also be used to talk about the scattering of something across a very large range, such as the dispersion of people with Scottish heritage across the United States. The Latin root word is dispersione, which means a scattering.

Example Sentences

But there has been substantial dispersion beneath the surface, Klar noted.

From MarketWatch • Mar. 31, 2026

“Indices have traded sideways, but dispersion has been historically high under the surface,” he notes.

From MarketWatch • Mar. 9, 2026

Among them are massless spin waves similar to graphene's electron waves, as well as low dispersion bands associated with localized states and even topological effects that span multiple bands.

From Science Daily • Mar. 8, 2026

Inflation uncertainty and wide dispersion in economic growth forecasts meant that even members who read the private signals clearly couldn’t build consensus to act on them.

From Barron's • Mar. 7, 2026

Within small areas the beetles accomplish their own dispersion, moving on as soon as the Klamath weed dies out and locating new stands with great precision.

From "Silent Spring" by Rachel Carson

Related Words

• diffusion