accretion

American  

[uh-kree-shuhn] / əˈkri ʃən /

noun

1. an increase by natural growth or by gradual external addition; growth in size or extent.

2. the result of this process.

3. an added part; addition.

   The last part of the legend is a later accretion.

4. the growing together of separate parts into a single whole.

5. Law. increase of property by gradual natural additions, as of land by alluvion.

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accretion British  

/ əˈkriːʃən /

noun

1. any gradual increase in size, as through growth or external addition

2. something added, esp extraneously, to cause growth or an increase in size

3. the growing together of normally separate plant or animal parts

4. pathol

   1. abnormal union or growing together of parts; adhesion

   2. a mass of foreign matter collected in a cavity

5. law an increase in the share of a beneficiary in an estate, as when a co-beneficiary fails to take his share

6. astronomy the process in which matter under the influence of gravity is attracted to and increases the mass of a celestial body. The matter usually forms an accretion disc around the accreting object

7. geology the process in which a continent is enlarged by the tectonic movement and deformation of the earth's crust

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accretion Scientific  

/ ə-krē′shən /

1. Geology The gradual extension of land by natural forces, as in the addition of sand to a beach by ocean currents, or the extension of a floodplain through the deposition of sediments by repeated flooding.

2. Astronomy The accumulation of additional mass in a celestial object by the drawing together of interstellar gas and surrounding objects by gravity.

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Other Word Forms

• accretionary adjective
• accretive adjective
• nonaccretion noun

Etymology

Origin of accretion

First recorded in 1605–15; from Latin accrētiōn- (stem of accrētiō ), equivalent to accrēt(us), past participle of accrēscere “to grow” ( ac- prefix meaning “toward” + crē- “grow” + -tus past participle suffix) + -iōn- noun suffix; ac-, -ion

Example Sentences

A new study presents the most detailed and complete model yet of luminous black hole accretion, the process by which black holes pull in surrounding matter and emit intense radiation.

From Science Daily

These new measurements support a key prediction of general relativity and could help scientists investigate black hole spin, accretion physics, and how jets form.

From Science Daily

One possible explanation for the ultraluminosity is that an extraordinary amount of gas falls onto a compact object through a process called supercritical accretion.

From Science Daily

Forming such a galaxy involves slow, steady gas accretion, the settling of that gas into a rotating disk, and the emergence of density waves that sculpt spiral arms.

From Science Daily

Active galactic nuclei occur when material spirals into a galaxy's central black hole, forming an extremely hot accretion disk.

From Science Daily

Related Words

• accumulation