Aviation student's aptitude score

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
"nine-point scale for test scores," introduced by the U.S. Air Force in 1942, from sta(ndard) + nine .

Wikipedia Word definitions in Wikipedia
Stanine (STAndard NINE) is a method of scaling test scores on a nine-point standard scale with a mean of five and a standard deviation of two. Some web sources attribute stanines to the U.S. Army Air Forces during World War II . Psychometric legend has ...