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

Epstein has paid millions of dollars in civil compensation that, for the most part, has kept the details about his operation out of the public eye. Julie K. Brown, The Seattle Times, "Perversion of Justice: Even from jail, sex abuser manipulated the system. His victims were kept in the dark," 4 Dec. 2018 Two-hundred and fifty major brands including Coca-Cola, Kellogg’s, and Nestle have pledged to cut all plastic waste from their operations. Tyler Wetherall, Condé Nast Traveler, "The All-Women Sailing Crew Trying to Save the Ocean of Plastic," 27 Nov. 2018 As the issue becomes more and more dangerous to the environment, a growing list of companies are looking to become more sustainable in their operations—especially those in the fashion and beauty industries. Lauren Alexis Fisher, Harper's BAZAAR, "Burberry, H&M, L'Oreal and More Sign on to Address Global Plastic Crisis," 29 Oct. 2018 While these restaurant chains all plan on opening their doors, specific hours of operation vary by region. Amanda Garrity, Good Housekeeping, "18 Restaurants Open on Thanksgiving This Year," 16 Oct. 2018 The dress featured a V-neck back, which Princess Eugenie wanted to wear to show the scars from her childhood scoliosis operation. Christopher Rosa, Glamour, "Princess Charlotte and Prince George Stole the Show at Princess Eugenie's Royal Wedding," 12 Oct. 2018 The boat resumed its operation after acquiring a Panama flag. Samuel Petrequin, Fox News, "Charities operating migrant rescue ship ask Europe for help," 24 Sep. 2018 In the caption, Dunham explained the significance of the progress she's made since her November operation. Andrea Park, SELF, "Lena Dunham Celebrates the 9-Month Anniversary of Her Hysterectomy With a Heartfelt Instagram Post," 15 Aug. 2018 During the firm’s short lifespan, from 1950, when Eero took over from his talented father and fellow architect, Eliel, to 1961, when Eero unexpectedly and tragically died during an operation, its work established Saarinen as a legend. Patrick Sisson, Curbed, "Why Eero Saarinen’s ‘50s office was a breeding ground for modernist design," 8 Nov. 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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Statistics for operation

Last Updated

11 Dec 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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to enclose within walls

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