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Brownian movement

[brou-nee-uh n]

noun Physics.

the irregular motion of small particles suspended in a liquid or a gas, caused by the bombardment of the particles by molecules of the medium: first observed by Robert Brown in 1827.

Origin of Brownian movement

1870–75; Brown + -ian
Also called Brownian motion.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for brownian motion

Brownian movement

noun

random movement of microscopic particles suspended in a fluid, caused by bombardment of the particles by molecules of the fluid. First observed in 1827, it provided strong evidence in support of the kinetic theory of molecules

Word Origin for Brownian movement

C19: named after Robert Brown
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for brownian motion

Brownian movement

n.

1871, for Scottish scientist Dr. Robert Brown (1773-1858), who first described it.

Online Etymology Dictionary, © 2010 Douglas Harper
brownian motion in Medicine

Brownian movement

[brŏu′nē-ən]

n.

The random movement of microscopic particles suspended in a liquid or gas, caused by collisions with molecules of the surrounding medium.Brownian motion molecular movement pedesis
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
brownian motion in Science

Brownian motion

[brou′nē-ən]

The random movement of microscopic particles suspended in a liquid or gas, caused by collisions between these particles and the molecules of the liquid or gas. This movement is named for its identifier, Scottish botanist Robert Brown (1773-1858). See also kinetic theory.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
brownian motion in Culture

Brownian motion

The erratic motion, visible through a microscope, of small grains suspended in a fluid. The motion results from collisions between the grains and atoms or molecules in the fluid.

Note

Brownian motion was first explained by the twentieth-century physicist Albert Einstein, who considered it direct proof of the existence of atoms.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.