Accretion

an increase by natural growth or by gradual external addition; growth in size or extent.
the result of this process.
an added part; addition:
the last part of the legend is a later accretion.
the growing together of separate parts into a single whole.
law. increase of property by gradual natural additions, as of land by alluvion.
contemporary examples

the powerful forces of gravity and magnetism channel matter into huge flattened spinning platters known as accretion disks.
the black hole tango matthew r. francis november 23, 2014

the accretion of interest groups is not a uniquely american problem.
so what would i do about china? david frum august 21, 2012

the direction of polarization for a quasar is determined by the accretion disk surrounding it.
the black hole tango matthew r. francis november 23, 2014

their gravitational pull can draw in huge amounts of gas, which swirls in a thick donut-shaped pattern known as an accretion disk.
the superm-ssive black hole smokescreen matthew r. francis june 21, 2014

historical examples

the appearance greatly improved, and the accretion in seven years after thinning showed 160 per cent.
garden and forest weekly, volume 1 no. 1, february 29, 1888 various

with any accretion allowed, the concentration of wealth is irresistible.
usury calvin elliott

organisms are not added to by accretion, as in the case of minerals, but by growth.
natural law in the spiritual world henry drummond

the only difficulty in this accretion is to secure debtors that will not die.
usury calvin elliott

nor must we despise them when we reflect upon their power of accretion.
lippincott’s magazine of popular literature and science, vol. xii, no. 28. july, 1873. various

she was in a state of rare contentment, an accretion to the gaiety that was hers by nature.
the intrusions of peggy anthony hope

noun
any gradual increase in size, as through growth or external addition
something added, esp extraneously, to cause growth or an increase in size
the growing together of normally separate plant or animal parts
(pathol)

abnormal union or growing together of parts; adhesion
a m-ss of foreign matter collected in a cavity

(law) an increase in the share of a beneficiary in an estate, as when a co-beneficiary fails to take his share
(astronomy) the process in which matter under the influence of gravity is attracted to and increases the m-ss of a celestial body. the matter usually forms an accretion disc around the accreting object
(geology) the process in which a continent is enlarged by the tectonic movement and deformation of the earth’s crust
n.

1610s, from latin accretionem (nominative accretio) “an increasing, a growing larger” (e.g. of the waxing moon), noun of action from past participle stem of accrescere, from ad- “to” (see ad-) + crescere “grow” (see crescent).

accretion ac·cre·tion (ə-krē’shən)
n.

growth or increase in size by gradual external addition, fusion, or inclusion.

increase by addition to the periphery of material of the same nature as that already present, as in the growth of crystals. also called accrement-tion.

foreign material, such as plaque or calculus, collecting on the surface of a tooth or in a cavity.

the growing together or adherence of body parts that are normally separate.

accretion
(ə-krē’shən)

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.

astronomy the acc-mulation of additional m-ss in a celestial object by the drawing together of interstellar gas and surrounding objects by gravity.