op·er·a·tion | \ ˌä-pə-ˈrā-shən \

Definition of operation 

1 : performance of a practical work or of something involving the practical application of principles or processes Practice until you can go through the whole operation without hesitation or thinking.

2a : an exertion of power or influence the operation of a drug

b : the quality or state of being functional or operative The plant is now in operation.

c : a method or manner of functioning a machine of very simple operation

3 : efficacy, potency archaic except in legal usage

4 : a procedure performed on a living body usually with instruments especially for the repair of damage or defect or the restoration of health needed an operation to remove his appendix

5 : any of various mathematical or logical processes (such as addition) of deriving one entity from others according to a rule Multiplication is one mathematical operation.

6a : a usually military action, mission, or maneuver including its planning and execution military operations for a large-scale invasion

b operations plural : the office on the flight line of an airfield where pilots file clearance for flights and where flying from the field is controlled

c operations plural : the agency of an organization charged with carrying on the principal planning and operating functions of a headquarters and its subordinate units

7 : a business transaction especially when speculative continued his operations in cotton futures

8 : a single step performed by a computer in the execution of a program (see program entry 1 sense 6a)

9 : a usually small business or establishment ran a struggling operation

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Examples of operation in a Sentence

The family runs a small farming operation. The company is a billion-dollar operation.

Recent Examples on the Web

Berrada told the aldermen there were only about 30 vacancies in the 8,000 rental units nationwide his operation owned. Kevin Crowe, Milwaukee Journal Sentinel, "'He'll evict you in a minute.' Landlord quietly becomes a force in Milwaukee rental business...and eviction court," 13 July 2018 Bridgford Foods, maker of jerky and sausage, is in the process of moving its operations to a larger and more efficient building in Back of the Yards. Ryan Ori, chicagotribune.com, "In exodus from Fulton Market, surviving meatpackers scatter and adapt," 13 July 2018 There’s definitely a market for retailers that have closed their operations. Patrick Danner, San Antonio Express-News, "San Antonio Zoo’s efforts to ‘adopt’ Toys R Us mascot might be a stretch," 13 July 2018 The American Bankers Association, which has spent months overhauling its political operations, for the first time is running television ads in support of incumbent lawmakers from both parties who have backed industry-friendly policies. Tory Newmyer, Washington Post, "The Finance 202: Mnuchin is in denial about the pain Trump's tariffs are inducing," 13 July 2018 Despite being a component unit of government that residents pay annual taxes to support, the village board has largely ignored the library and its operations until recently, Denson said. Zak Koeske, Daily Southtown, "For years, there's been no financial oversight at the Calumet Park library. Now the state is getting involved.," 13 July 2018 After one of Uber’s cars struck and killed a pedestrian, various revelations have cast its self-driving operations — and its backup drivers — in a harsh light. Carolyn Said, SFChronicle.com, "Uber lays off 100 backup drivers in self-driving unit," 12 July 2018 Businesses are bracing for this scenario, with international firms making preparations to shift their operations elsewhere to mitigate the impact. Jonah Shepp, Daily Intelligencer, "The Brexit Crisis Finally Engulfs the Party That Started It," 11 July 2018 Later, Uber laid off around 300 of its safety operators in Arizona and shuttered its autonomous driving operation in the state. Andrew J. Hawkins, The Verge, "Uber laid off its self-driving car safety drivers in Pittsburgh," 11 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'operation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of operation

14th century, in the meaning defined at sense 1

History and Etymology for operation

Middle English operacion "work, action, procedure performed on a body, functioning," borrowed from Medieval Latin operātiōn-, operātiō, going back to Latin, "application of effort, functioning (of natural forces)," from operārī "to busy oneself, be at work" + -tiōn-, -tiō, suffix of action nouns — more at operate

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Phrases Related to operation

base of operations

sex change (operation)

Statistics for operation

Last Updated

18 Sep 2018

Look-up Popularity

Time Traveler for operation

The first known use of operation was in the 14th century

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More Definitions for operation



English Language Learners Definition of operation

: a process in which a doctor cuts into someone's body in order to repair or remove a damaged or diseased part

: a usually small business or organization

: an activity of a business or organization


op·er·a·tion | \ ˌä-pə-ˈrā-shən \

Kids Definition of operation

1 : a set of actions for a particular purpose a rescue operation

2 : a medical procedure that involves cutting into a living body in order to repair or remove a damaged or diseased part I need an operation to remove my appendix.

3 : the process of putting military forces into action naval operations

4 : the state of working or being able to work The factory is now in operation.

5 : a method or manner of working The camera is designed for easy operation.

6 : a process (as addition or multiplication) of getting one mathematical expression from others according to a rule

7 : a single step performed by a computer in carrying out a program


op·er·a·tion | \ ˌäp-ə-ˈrā-shən \

Medical Definition of operation 

: a procedure performed on a living body usually with instruments for the repair of damage or the restoration of health and especially one that involves incision, excision, or suturing

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Comments on operation

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alleviating pain or harshness

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