Student's t

noun
  1. a statistic often used to test the hypothesis that a random sample of normally distributed observations has a given mean, μ; given by t = (̄x– μ) √n/s where ̄x is the mean of the sample, s is its standard deviation, and n is the size of the sample

Word Origin for Student's t

after Student, the pen name of W. S. Gosset (1876–1937), English statistician and research scientist
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