(dated, countable) Calculation; computation. / (countable, mathematics) Any formal system in which symbolic expressions are manipulated according to fixed rules.

(computing theory) Any of a family of functionally complete algebraic systems in which lambda expressions are evaluated according to a fixed set of rules to produce values, which may themselves be lambda expressions.

(calculus) The calculus that deals with instantaneous rates of change.

(calculus) The calculus that generalizes summation to find areas, masses, volumes, sums, and totals of quantities described by continuously varying functions.

(calculus) Differential calculus and integral calculus considered together as a single subject.

(logic) The branch of logic that deals with quantified statements such as "there exists an x such that..." or "for any x, it is the case that...", where x is a member of the domain of discourse.

A hard crust of calcium salts and food particles on the teeth, developing from plaque.

(calculus) The form of calculus that deals with the maxima and minima of definite integrals of functions of many variables.

(logic) A formal system.

(logic) propositional logic.