accretion disk
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noun Astronomy.
the rapidly spinning disk of gas that forms around the more compact component of a close binary star system as mass is transferred to the compact companion from the primary star.
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Let’s start with some etymology: What are the origins of the typographical word “bracket”?
First appeared around 1750, and is related to the French word “braguette” for the name of codpiece armor.
First appeared in 1610, based on the French word “baguette” for the long loaf of bread.
First appeared in 1555, and is related to the French word “raquette” for a netted bat.
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Origin of accretion disk
First recorded in 1975–80
Words nearby accretion disk
accrete, accretio cordis, accretion, accretionary growth, accretionary wedge, accretion disk, accretive, Accrington, accroach, accroides gum, accrual
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
Example sentences from the Web for accretion disk
Scientific definitions for accretion disk
accretion disk
A spinning disk of gas and dust surrounding a celestial object with an intense gravitational field, such as a star or a black hole. In binary star systems, the gravitational attraction of the denser star can pull matter from the other star into an accretion disk in its own orbit. The material in the accretion disk eventually spirals into the attracting star and adds to its mass. The gas in accretion disks that surround black holes becomes condensed and heated as it is sucked into the hole, emitting x-rays and other radiation that provide evidence for the presence of the black hole.
The American Heritage® Science Dictionary
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