Statistical Glossary
Stanine:
A stanine is a "standard ninth," an interval used in dividing school test results into (more or less) ninths. Stanine 1 includes all scores less than 1.75 standard deviations below the mean, and stanine 9 all scores more than 1.75 standard deviations above the mean. Stanines 2-8 are each 1/2 of a standard deviation wide, so the mean falls in the center of stanine 5.