calculus

noun6

1. •
   Any formal system in which symbolic expressions are manipulated according to fixed rules.
2. •
   Differential calculus and integral calculus considered as a single subject.

   • I took calculus in high school.
3. •
   A decision-making method, especially one appropriate for a specialised realm.

   • The Tory leader refused to state how many financiers he thought should end up in jail, saying: “There is not some simple calculus." — 2008
4. •
   (old-fashioned) Calculation; computation.
5. •
   A stony concretion that forms in a bodily organ.
6. •
   Deposits of calcium phosphate salts on teeth.