Yes in Latin

Allen & Greenough, New Latin Grammar § 336: "There is no one Latin word in common use meaning simply yes or no." On ways around this lack, see H. Thesleff, Yes and No in Plautus and Terence (Helsinki, 1960) = Societas Scientiarum Fennica. Commentationes humanarum litterarum, XXVI, 3.

Cf. Anthony Burgess, Little Wilson and Big God (1987; rpt. New York: Grove Weidenfeld, 1991), p. 100:

Burgess swore that there was a Latin word for yes unrecorded in Roman literature. This, he said, was chut and derived from the sneezing of Caligula. When Caligula sneezed at the games, it was interpreted ambiguously -- yes, let him die; yes, let him live. Because the meanings cancelled out, chut did not survive.

The imaginative Burgess of this anecdote was James Burgess, no relation to Anthony Burgess, the nom de plume of John Burgess Wilson.