This is a historical and lighthearted question about etymology.
The area of mathematics that deals with limiting processes over real numbers (Real Analysis) or real vector spaces, or even complex vector spaces (I think it depends on who you ask) is variably referred to as "analysis" or "the Calculus".
My question is, why did this particular area of math get the somewhat grandiose name The Calculus, which, if taken literally, means something like "The way to reason". It seems like linear algebra, geometry, logic, and many other formal systems are just as worthy of this title in their areas of application, yet the mathematics that was developed by Newton, Leibniz, Weierstrass & Co. has taken this moniker without contest.
Any anyone fill in the history of why this particular branch of mathematics got this title? I know calculus is a great achievement, has lots of applications, etc...but I don't think that is the reason.
Half-jokingly, maybe it was just good marketing on the developers of Calculus...give it a great name so people pay attention to it ;-)