Tim Peters added the comment: One more useless ;-) data point, from Macsyma: ? acosh; -- Function: acosh (<x>) - Hyperbolic Arc Cosine. I don't like "area" - while accurate, nobody else uses it. Gratuitous novelty is no virtue ;-) I like "inverse" better than "arc", because it's all of accurate, common, and nearly self-evident. ---------- nosy: +tim.peters _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue21902> _______________________________________