operation

American  

[op-uh-rey-shuhn] / ˌɒp əˈreɪ ʃən /

noun

1. an act or instance, process, or manner of functioning or operating.

2. the state of being operative (usually preceded by in orinto ).

   a rule no longer in operation.

3. the power to act; efficacy, influence, or force.

4. the exertion of force, power, or influence; agency.

   the operation of alcohol on the mind.

5. a process of a practical or mechanical nature in some form of work or production.

   a delicate operation in watchmaking.

6. a course or procedure of productive or industrial activity.

   building operations.

7. a particular process or course.

   mental operations.

8. a business transaction, especially one of a speculative nature; deal.

   a shady operation.

9. a business, especially one run on a large scale.

   a multinational operation.

10. Surgery. a procedure aimed at restoring or improving the health of a patient, as by correcting a malformation, removing diseased parts, implanting new parts, etc.

11. Mathematics.

    1. a mathematical process, as addition, multiplication, or differentiation.

    2. the action of applying a mathematical process to a quantity or quantities.

12. Computers. any discrete activity or action that is performed by a computer, as reading, writing, processing, sending, or receiving data.

    The http request operation has timed out.

13. Military.

    1. a campaign, mission, maneuver, or action.

    2. Usually operations the conduct of a campaign, mission, etc.

    3. operations, a headquarters, office, or place from which a military campaign, air traffic to and from an airfield, or any of various other activities, is planned, conducted, and controlled.

    4. operations, the people who work at such a headquarters.

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operation British  

/ ˌɒpəˈreɪʃən /

noun

1. the act, process, or manner of operating

2. the state of being in effect, in action, or operative (esp in the phrases in or into operation )

3. a process, method, or series of acts, esp of a practical or mechanical nature

4. surgery any manipulation of the body or one of its organs or parts to repair damage, arrest the progress of a disease, remove foreign matter, etc

5. 1. a military or naval action, such as a campaign, manoeuvre, etc

   2. ( capital and prenominal when part of a name )

      Operation Crossbow

6. maths

   1. any procedure, such as addition, multiplication, involution, or differentiation, in which one or more numbers or quantities are operated upon according to specific rules

   2. a function from a set onto itself

7. a commercial or financial transaction

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operation Scientific  

/ ŏp′ə-rā′shən /

1. Medicine A surgical procedure for remedying an injury, ailment, defect, or dysfunction.

2. Mathematics A process or action, such as addition, substitution, transposition, or differentiation, performed in a specified sequence and in accordance with specific rules.

3. A logical operation.

4. Computer Science An action resulting from a single instruction.

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Other Word Forms

• misoperation
  noun
• preoperation
  noun
• reoperation
  noun
• suboperation
  noun

Etymology

Origin of operation

First recorded in 1350–1400; Middle English operacioun, oparacion, operation, from Latin operātiōn- (stem of operātiō ), equivalent to operāt(us) + -iōn- noun suffix of action or condition; see origin at operate

Explanation

Operation can refer to medical surgery, a military campaign, or mathematical methods, such as multiplication and division. Operation comes from the Latin word opus (“work”) and can refer to a whole range of practical activities and work. In driver's education, you learn the proper operation of a motor vehicle. If you’re going to make your lemonade franchise a success, you’re going to have to learn the rules for prudent operation of a business — how to run it — and you’ll also have to figure out the operation of a lemon squeezer.

Example Sentences

"We remain as steadfast as ever in our resolve to defeat terrorism and destroy its enabling ecosystem," Modi said on Thursday, a year on since the launch of what India dubbed "Operation Sindoor".

From Barron's • May 7, 2026

US Secretary of State Marco Rubio said earlier Tuesday that the United States has completed its offensive operations against Iran, which it dubbed "Operation Epic Fury".

From Barron's • May 5, 2026

The internal debate over resuming the war comes after Pentagon officials informed Congress this week that the conflict, dubbed Operation Epic Fury, had cost taxpayers $25 billion thus far.

From Los Angeles Times • May 2, 2026

Bases in the country have served as key logistics hubs and fueling stops for Operation Epic Fury, as the U.S. military campaign against Iran is known.

From The Wall Street Journal • May 1, 2026

With faith in Operation Breakthrough, a hundred residents formed a new organization—the Tenants’ Club—to handle grievances with the DHA.

From "The Best of Enemies" by Osha Gray Davidson

Related Words

• action
• activity
• affair
• agency
• application
• deal
• effort
• enterprise
• exercise
• force
• movement
• procedure
• process
• service
• transaction
• trip
• use
• work