Constant small movement of suspended particles due to bombardment by surrounding molecules

Brownian motion is the continuous random movement of small particles suspended in a fluid, which arise from collisions with the fluid molecules. First observed by the British botanist R. Brown (1773-1858) when studying pollen particles. The effect is also visible in particles of smoke suspended in a still gas.

(Also called Brownian movement.) The rapid and chaotic motion of particles suspended in a fluid at rest as a consequence of fluctuations in the rate at which fluid molecules collide with the particles. On average, the particles experience zero net force, but deviations from this average give rise to Brownian motion, so named because it reputedly was observed first in pollen grains by the botanist Robert Brown. Whether Brown actually observed what we now call Brownian motion has been questioned on the grounds that his grains were so large that their fluctuating motion would have been imperceptible. But even if Brownian motion can ever be shown not to have been observed by Brown, his name is likely to be forever attached to this motion, especially since mathematicians have generalized this term to a broad class of stochastic processes. Brownian motion is more than just a scientific curiosity, having played a key role in establishing the reality of molecules and in presenting a convincing argument for the kinetic theory of gases. Boorse, H. A., and L. Motz, 1966: The World of the Atom, Vol. I, 206–212.

The archetypal random motion observed by botanist Robert Brown in 1828 of pollen grains in water. Variants of this are used as the assumed path of securities prices in many financial models.

A random movement of microscopic particles suspended in liquids or gases resulting from impact of the molecules of the suspending agent on the particles.

the random motion of small particles suspended in a gas or liquid

The continual motion of extremely small particles suspended in a fluid, given energy by molecular bombardment.

Random motion of particles due to collisions with gas molecules.1

Brownian motion is the name given to the random movement of small particles floating in still air or suspended in water. This random motion occurs because they are constantly being bombarded by the molecules of the surrounding gas or liquid. Particles of Matter

The continuous zig-zag motion of suspended minuscule particles. The motion is caused by impact of the molecules in the fluid upon the particles.

Agitated movement of suspended colloidal particles, when a colloidal dispersion is examined using a light microscope at high magnification. This motion is caused by collision with the molecules of the continuous phase; the rate and extent of Brownian movement increases at higher temperatures.

Very tiny particles in a liquid, when highly magnified, can be seen to dance around, vibrating at random. This motion is caused by the impact of molecules hitting them randomly on all sides. It is an indirect observation of heat working at the atomic level.

Motion of a particle in a fluid owing to thermal agitation, observed in 1827 by Robert Brown. (Originally thought to be caused by vital force, Brownian motion in fact plays a vital role in the assembly and activity of the molecular structures of life)

The irregular motion of solid particles in a fluid caused by the consistent random collisions with individual molecules of the fluid.

Brownian movement. Small particles suspended in liquid move spontaneously in a random fashion. The motion is caused by unbalanced impacts of molecules on the particle. Brownian motion provided strong circumstantial evidence for the existence of molecules.

the movement of microscopic particles caused by Brownies

With apologies to Douglas Adams, the best example is indeed a really hot cup of tea. It has to do with internal movement within a hot liquid.

A simple continuous stochastic process that is widely used in physics and finance for modeling random behavior that evolves over time.

The random motion of microscopic particles suspended in a liquid or gas, caused by collision with molecules of the surrounding medium. Also called "Brownian movement."

Describes a pattern of random movement of particles in liquids or gases the terminal part of the gut in most vertebrates except the higher mammals