Noun

(en noun)

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 .

The method or practice by which actions are done.

The act or process of operating; agency; the exertion of power, physical, mechanical, or moral.

* John Locke

The pain and sickness caused by manna are the effects of its operation on the stomach.

* Dryden

Speculative painting, without the assistance of manual operation , can never attain to perfection.

A planned undertaking.

The police ran an operation to get vagrants off the streets.

The ''Katrina'' relief operation was considered botched.

A business or organization.

We run our operation from a storefront.

They run a multinational produce-supply operation .

(medicine) a surgical procedure.

She had an operation to remove her appendix.

(computing, logic, mathematics) a procedure for generating a value from one or more other values (the operands).

(military) a military campaign (e.g. )

(obsolete) Effect produced; influence.

* Fuller

The bards had great operation on the vulgar.

Noun

(en noun)

A device used to produce music.

The violinist was a master of her instrument .

A means or agency for achieving an effect.

* {{quote-book, year=1905, author=

, title= , chapter=1 citation , passage=“There the cause of death was soon ascertained?; the victim of this daring outrage had been stabbed to death from ear to ear with a long, sharp instrument , in shape like an antique stiletto, which […] was subsequently found under the cushions of the hansom. […]”}}

A measuring or displaying device.

The instrument detected an increase in radioactivity.

A tool, implement used for manipulation or measurement.

The dentist set down his tray of instruments'''.'' The scientist recorded the temperature with a thermometer but wished he had a more accurate ' instrument ."

(legal) A legal document, such as a contract, deed, trust, mortgage, power, indenture, or will.

A bond indenture is the instrument that gives a bond its value.

Negotiable instruments are the foundation of the debt markets.

(figuratively) A person used as a mere tool for achieving a goal.

* Shakespeare

Or useful serving man and instrument , / To any sovereign state.

* Dryden

The bold are but the instruments of the wise.