Poisson distribution

[ pwah-sohn; French pwa-sawn ]
/ pwɑˈsoʊn; French pwaˈsɔ̃ /

noun Statistics.

a limiting form of the binomial probability distribution for small values of the probability of success and for large numbers of trials: particularly useful in industrial quality-control work and in radiation and bacteriological problems.

Origin of Poisson distribution

1920–25; named after S. D. Poisson (1781–1840), French mathematician and physicist
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for poisson distribution

Poisson distribution
/ (ˈpwɑːsən) /


statistics a distribution that represents the number of events occurring randomly in a fixed time at an average rate λ; symbol P 0 (λ). For large n and small p with np = λ it approximates to the binomial distribution Bi (n,p)

Word Origin for Poisson distribution

C19: named after S. D. Poisson
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

Science definitions for poisson distribution

Poisson distribution
[ pwä-sôɴ ]

A probability distribution which arises when counting the number of occurrences of a rare event in a long series of trials. It is named after its discoverer, French mathematician and physicist Siméon Denis Poisson (1781-1840).
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.