operation

noun10

1. •
   The act or process of operating (verb): agency; the exertion of power, physical, mechanical, or moral.

   • the pain and sickness caused by manna are confessedly nothing but the effects of its operations on the stomach and guts. — 1689
2. •
   a treatment for a health problem, done by cutting into the body, usually in a hospital

   • She had an operation to remove her appendix.
3. •
   A planned undertaking.

   • The police ran an operation to get vagrants off the streets.
   • The Katrina relief operation was considered botched.
4. •
   A military campaign (e.g. Operation Desert Storm).
5. •
   The method by which a device performs its function.

   • It is dangerous to look at the beam of a laser while it is in operation.
6. •
   The method or practice by which actions are done.
7. •
   A business or organization.

   • We run our operation from a storefront.
   • They run a multinational produce-supply operation.
8. •
   A procedure for generating a value from one or more other values (the operands).

   • The number of operands associated with an operation is called its arity; an operation of arity 2 is called a binary operation.
9. •
   A function which maps zero or more (but typically two) operands to a single output value.
10. •
    (no longer used) Effect produced; influence.

    • The bards […] had great operation on the vulgar. — 1655