From Longman Dictionary of Contemporary Englishstandard deviationˌstandard deviˈation noun [countable] technicalHMS a number in statistics that shows by how much members of a mathematical set can be different from the average set

Examples from the Corpus

standard deviation• Mean and standard deviation of normally distributed results are shown; otherwise median and range are given.• The distribution remains normal but the standard deviation decreases as the square root of n, the sample size.• The standard deviation of the estimate of, B is calculated as follows: therefore, the standard deviation is:.From Longman Business Dictionarystandard deviationˌstandard deviˈation [countable]STATISTICS a number that shows how widely members of a mathematically related group vary from the averageVolatility as measured by the standard deviation of daily stock price movements has frequently been much higher than it is today. → deviation