Definition of: operation

(op′ə·rā′shən) noun
1. The act or process of operating; the exertion or action of any form of power or energy.
2. A method of exercising or applying force; a mode of action.
3. A single specific act or transaction, especially in the stock market.
4. A course or series of acts to effect a certain purpose; process.
5. The state of being in action: The machinery is in operation.
6. Surg. Any systematic manipulation upon the body, performed either with or without instruments, to restore disunited or deficient parts, to remove diseased or injured parts, or to extract foreign matter.
7. Math. a The act of making a change in the value or form of a quantity. b The change itself as indicated by symbols or rules: distinguished from the process by which such change is accomplished.
8. Some special kind of activity; manner of action; a vital or natural process of activity.
9. A military or naval campaign. Synonyms: action, agency, effect, execution, force, influence, performance, procedure, result. Operation is action resulting in change, whether produced by the agency or action of an intelligent agent or of a material substance or force; as, military operations; the operation of a medicine. Performance and execution denote intelligent action, considered with reference to the actor or to that which he accomplishes; performance accomplishing the will of the actor, execution often the will of another. Compare ACT, EXERCISE. Antonyms: failure, inaction, ineffectiveness, inefficiency, inutility, powerlessness.