Brownian motion

noun Brown·ian motion \ ˈbrau̇-nē-ən- \

Definition of Brownian motion

: a random movement of microscopic particles suspended in liquids or gases resulting from the impact of molecules of the surrounding medium — called also Brownian movement

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Origin and Etymology of brownian motion

Robert Brown †1858 Scottish botanist

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First Known Use: 1849

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Medical Dictionary

Brownian motion

noun Brown·ian motion \ ˌbrau̇-nē-ən- \

medical Definition of Brownian motion

: a random movement of microscopic particles suspended in liquids or gases resulting from the impact of molecules of the fluid surrounding the particles — called also Brownian movement

Biographical Note for brownian motion

Brown play \ˈbrau̇n\, Robert (1773–1858), British botanist. Brown was one of the leading botanists of his day. In 1801 he accompanied a surveying expedition to and around Australia, acting as the company's naturalist. In 1805 he returned to Great Britain with about 3,900 species of plants, and in 1810 he published a great work on the flora of Australia. In the field of botany he is also known for his substantial contributions to plant morphology, embryology, and geography, for improving plant classification and making a fundamental distinction between gymnosperms and angiosperms, for establishing and defining new families and genera, and for describing and naming the nucleus of a plant cell. He published his observations on Brownian motion in 1831.