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Type II error

noun
  1. the error made in the statistical testing of a hypothesis by accepting the null hypothesis when it is actually false.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for type ii error

type II error

noun
  1. statistics the error of not rejecting the null hypothesis when it is false. The probability of avoiding such an error is the power of the test and is a function of the alternative hypothesis
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