calculus
/ˈkæl.kjʊ.ləs/
Calculation; computation.
Any formal system in which symbolic expressions are manipulated according to fixed rules.
lambda calculus
(often definite, the calculus) Differential calculus and integral calculus considered as a single subject; analysis.
A stony concretion that forms in a bodily organ.
renal calculus ( = kidney stone)
Deposits of calcium phosphate salts on teeth.
A decision-making method, especially one appropriate for a specialised realm.