An Etymological Dictionary of Astronomy and Astrophysics

A measure of the scatter of the values of a random variable (X) about its mean (μ). Var(X) = E(X -μ)². The positive square root of the variance is called the → standard deviation.

Etymology (EN): M.E., from O.Fr. variance, from L. variantia, from variare “to change,” → vary.

Etymology (PE): Vartâyi quality noun from vartâ agent noun from vartidan, → vary.