Brownian motion

[ brou-nee-uhn moh-shuhn ]

/ ˈbraʊ ni ən ˈmoʊ ʃən /

Save This Word!

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 Scottish botanist Robert Brown in 1827.

QUIZ

CAN YOU ANSWER THESE COMMON GRAMMAR DEBATES?

There are grammar debates that never die; and the ones highlighted in the questions in this quiz are sure to rile everyone up once again. Do you know how to answer the questions that cause some of the greatest grammar debates?

Question 1 of 7

Which sentence is correct?

His boss, whom he admires, is waiting to meet with him about the big project.

His boss, who he admires, is waiting to meet with him about the big project.

TAKE THE QUIZ TO FIND OUT

Also called Brown·i·an move·ment

[brou-nee-uhn moov -muhnt]. /ˈbraʊ ni ən ˈmuv mənt/.

Origin of Brownian motion

1870–75; Brown + -ian

Words nearby Brownian motion

brownfield, brown goods, brown hackle, brown heart, brown hyena, Brownian motion, Brownian movement, brownie, Brownie Guide, Brownie Guider, Brownie point

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use Brownian motion in a sentence

I wonder what that lady is doing now, and if she knows what she set in motion with Archer?
‘Archer’ Creator Adam Reed Spills Season 6 Secrets, From Surreal Plotlines to Life Post-ISIS|Marlow Stern|January 8, 2015|DAILY BEAST
The train was already in motion as she tried to step inside, and her body was crushed beneath it.
Riding Thailand’s WWII Death Railway|Liza Foreman|December 21, 2014|DAILY BEAST
Stop-motion animation artist PES has unveiled a new short this week.
‘Sexual’ Barbershop Quartet, a Panda Family Reunion, and More Viral Videos|The Daily Beast Video|December 14, 2014|DAILY BEAST
But what he did set in motion a series of events that ended in his life being lost.
A Black Cop’s Tough Words for Mike Brown|Mary M. Chapman|December 3, 2014|DAILY BEAST

This year McQueen picked up three Oscars (including best picture) for his third motion picture 12 Years A Slave.
Has the Turner Prize Gone Soft?|David Levesley|December 2, 2014|DAILY BEAST
In this situation we waited the motion of the enemy, without perceiving any advancement they made towards us.
The Life and Most Surprising Adventures of Robinson Crusoe, of York, Mariner (1801)|Daniel Defoe
These sections also have vibrations of their own which are of shorter length and more rapid motion.
Expressive Voice Culture|Jessie Eldridge Southwick
Felipe watched over her as a lover might; her great mournful eyes followed his every motion.
Ramona|Helen Hunt Jackson
At six o'clock I felt once more the welcome motion of a Railroad car, and at eight was in Venice.
Glances at Europe|Horace Greeley
The first jolt had like to have shaken me out of my hammock, but afterwards the motion was easy enough.
Gulliver's Travels|Jonathan Swift

Scientific definitions for Brownian motion

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.

Cultural definitions for Brownian motion

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.

notes for Brownian motion

Brownian motion was first explained by the twentieth-century physicist Albert Einstein, who considered it direct proof of the existence of atoms.