operation

American  

[op-uh-ray-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

Staff working in news would argue it was the current affairs side of the operation that previously let the organisation down.

From BBC ● Oct. 5, 2026

Both main contracts fell Monday, extending Friday's drop, though the losses were pared by news that Yemen had started a new military operation to retake all territory held by the Houthis.

From Barron's ● Oct. 5, 2026

In an official statement, the department’s spokesperson said it “does not approve or deny the operation of microschools for any reason, including the qualifications of the owner/operator.”

From Salon ● Oct. 4, 2026

Previously the co-founder and chief executive of the data-labeling startup Scale AI, Wang has worked with Zuckerberg to build an operation that’s been viewed as putting Meta back in the thick of the AI race.

From The Wall Street Journal ● Oct. 2, 2026

Always before when pain from the gallstones had got too bad, she’d had an operation.

From "The Hiding Place" by Corrie ten Boom

In its announcement, GEO Group sad it will continue managing daily operations at the facilities under the company’s existing contract with U.S.

From Los Angeles Times ● Oct. 5, 2026

This is positive for rail operations of its subsidiary SBS Transit, with net revenue uplift for SBS Transit at around 18.8 million Singapore dollars, the analyst estimates.

From The Wall Street Journal ● Oct. 5, 2026

The tech mogul has since updated the hotels and added improvements to the island, such as some farming operations, with an eye toward turning the island into a sustainable mecca.

From MarketWatch ● Oct. 5, 2026

"Both operations successfully achieved their objectives," the spokesman said in a statement.

From BBC ● Oct. 4, 2026

Wringing his clothes, he made his way back to the birch, which had become his center of operations.

From "Abel's Island" by William Steig

Related Words

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