The Collaborative International Dictionary of English v.0.48:

Variate \Va"ri*ate\, v. t. & i. [L. variatus, p. p. of variare.
   See Vary.]
   To alter; to make different; to vary.
   [1913 Webster]

WordNet (r) 3.0 (2006):

variate
    n 1: a variable quantity that is random [syn: random variable,
         variate, variant, stochastic variable, chance
         variable]