Etymology

kurtosis

K5U1R1T1O1S1I1S1

Today it means: A measure of "heaviness of the tails" of a probability distribution, defined as the fourth cumulant divided by the square of the variance of the probability distribution. Full definition →

Ancient Greek κύρτωσις
Ask AI about its historyChatGPTClaudePerplexityGoogle AIGrok

The story

  1. Ancient Greek · derived fromκύρτωσις“a bulging, convexity”
  2. English todaykurtosis

Coined by English mathematician, biometrician, and eugenicist Karl Pearson c. 1895 (published 1899 in "On certain Properties of the Hypergeometrical Series, and so on the fitting of such series to Observation Polygons in the Theory of Chance", Phil. Mag.). From Ancient Greek κύρτωσις (kúrtōsis, “a bulging, convexity”), from κυρτός (kurtós, “bulging, convex”).

Etymology from Wiktionary, CC BY-SA 4.0.