dispersion

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The act or process of dispersing.
2. n. The state of being dispersed.
3. n. The Diaspora of the Jews.
4. n. Statistics The degree of scatter of data, usually about an average value, such as the median.
5. n. Physics Separation of a complex wave into its component parts according to a given characteristic, such as frequency or wavelength.
6. n. Physics Separation of visible light into colors by refraction or diffraction.
7. n. Chemistry See disperse system.

Century Dictionary and Cyclopedia

1. n. The act of dispersing or scattering.
2. n. The state of being dispersed or scattered abroad: as, the dispersion of the Jews.
3. n. In optics, the separation of the different colored rays in refraction, arising from their different, wave-lengths. The point of dispersion is the point where refracted rays begin to diverge. When a ray of sunlight is made to pass through prisms of different substances, but of such angles as to produce the same mean deviation of the ray, it is found that the spectra formed are of different lengths. Thus, the spectrum formed by a prism of oil of cassia is found to be two or three times longer than one formed by a glass prism; the oil of cassia is therefore said to disperse the rays of light more than the glass, or to have a greater dispersive power. It is also found that in spectra formed by prisms of different substances the colored spaces have to one another ratios differing from the ratios of the lengths of the spectra which they compose; and this property has been called the irrationality of dispersion or of the colored spaces in the spectrum. See prism and refraction.
4. n. In medicine and surgery, the scattering or removal of inflammation from a part and the restoration of the part to its natural state.
5. n. In mathematics, the excess of the average value of a function at less than an infinitesimal distance from a point over the value at that point, this excess being divided by 1/10 of the square of the limiting infinitesimal distance.
6. n. In physiol, optics, the blurring of the retinal image due to faulty accommodation.
7. n. In botany, the distribution of seeds and of plants by various means, as by the wind, by birds and animals, etc.
8. n. The tendency of material particles or bodies, including conscious individuals, to go apart, as from a center; hence, in the phenomena of population, the continual breaking down and dispersing of aggregations, counteracting a tendency toward concentration. See law of *aggregation.

Wiktionary

1. n. The state of being dispersed; dispersedness.
2. n. A process of dispersing.
3. n. The degree of scatter of data.
4. n. optics The separation of visible light by refraction or diffraction.
5. n. medicine The removal of inflammation.

GNU Webster's 1913

1. n. The act or process of scattering or dispersing, or the state of being scattered or separated
2. n. (Opt.) The separation of light into its different colored rays, arising from their different refrangibilities.

WordNet 3.0

1. n. the act of dispersing or diffusing something
2. n. the spatial or geographic property of being scattered about over a range, area, or volume
3. n. spreading widely or driving off