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

Little is known about the operation of his businesses. 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 Today, thanks to a lean operation of just two full-time employees, CONCIERGEpad is already profitable without any outside investment — though Perez does expect to seek investors for its national expansion. Rob Wile, miamiherald, "After mass shootings, schools turn to Miami-made app to keep out the bad guys," 13 July 2018 The City Council last week unanimously gave city staff its approval to continue to work on an agreement with Mundo Gardens for the operation of the garden, located on a quarter-acre plot on North Q Avenue. David Hernandez, sandiegouniontribune.com, "National City to move forward with plans for community gardens," 12 July 2018 The additional gates at the Lake Houston dam is the major project related to the lake that is currently proposed for the bond, according to Matt Zeve, Harris County Flood Control District director of operations. Melanie Feuk, Houston Chronicle, "Dam gates, dredging are major topics at county flood bond meeting in Kingwood," 12 July 2018 In fact, early in the operation one of the Thai rescuers, a former Thai Navy Seal, died after running out of oxygen, demonstrating how dangerous the rescue can be for rescuers. Bo Emerson, ajc, "Cave rescuers in Southeast watch their Thai colleagues with admiration," 10 July 2018 Westley Northrup, 30, and 10 others were charged in connection with the operation of the drug ring, authorities said. Ruth Bruno, courant.com, "Meriden Man Pleads Guilty To Operating Drug Ring While In Prison," 10 July 2018 Filling a need The Learning Lab started as a small operation of one teacher and four students. Michael Katz, idahostatesman, "A slain refugee was set to start preschool Monday. Despite tragedy, staffers carry hope.," 6 July 2018 And therefore, the operation of Megaupload couldn't be criminal copyright infringement. Timothy B. Lee, Ars Technica, "NZ court rules Kim Dotcom can be extradited to US on copyright charges," 5 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

16 Oct 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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