operation

American  

[op-uh-rey-shuhn] / ˌɒp əˈreɪ ʃən /

noun

• operations
  plural

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

Derived Forms

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

Inflected Forms

Nouns

• operations
  plural

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

See Examples For:

operation operations

During one recent overnight attack, AFP journalists were granted rare access to shadow "Esko", the channel's administrator, on condition that his identity and some details of the operation remained undisclosed.

From Barron's ● Aug. 16, 2026

Eighty families were forcibly evicted from a site at Dale Farm in an operation that concluded almost 15 years ago.

From BBC ● Aug. 15, 2026

Once we had those clues, we were able to search online archives of leaked computer data and unearth a much larger trove of information on the operation.

From The Wall Street Journal ● Aug. 14, 2026

Achieving this kind of cyclic operation has been an important objective for researchers working on quantum heat engines.

From Science Daily ● Aug. 14, 2026

Of course, Newcomen could have invented all this and more; after all, he worked on his new engine for some fourteen years before he was ready to put it into public operation.

From "The Invention of Science" by David Wootton

There was, however, a bit of good news this summer when Stellantis decided to allocate production of the next-generation Opel Astra and DS4 to Ruesselsheim, securing the plant's operations beyond 2029.

From Barron's ● Aug. 16, 2026

Union leaders are asking David Ellison commit to keeping Paramount’s operations in Hollywood and maintaining historic levels of film production in the U.S.

From Los Angeles Times ● Aug. 15, 2026

Earlier this week, Kalshi, a rival prediction market, was ordered to cease most operations in Washington state.

From The Wall Street Journal ● Aug. 14, 2026

The Lincoln has docked just twice since it left San Diego, and its crew has sometimes supported nonstop combat operations for weeks straight.

From Slate ● Aug. 14, 2026

It was shortly after the measles epidemic that Dad started applying motion study to surgery to try to reduce the time required for certain operations.

From "Cheaper by the Dozen" by Frank B. Gilbreth Jr. and Ernestine Gilbreth Carey

Related Words

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