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

This is not some CSI-style procedural, where catching murderers is a high-tech, bloodless, impersonal operation. Noel Murray, The Verge, "This weekend, stream some ‘Nordic noir’ on Netflix, starting with Deadwind," 9 Nov. 2018 Cruiskeen is a mostly one-person operation that sometimes uses freelance consultants, according to its website. Jack Gillum And Jeff Kao, Ars Technica, "File-sharing software on state election servers could expose them to intruders," 5 Nov. 2018 At the time, Rhodes had a small operation but was fast becoming one of the foremost designers of romantic, colorful frocks in the world. Brooke Bobb, Vogue, "Ahead of the Release of Bohemian Rhapsody, Zandra Rhodes Models the Wedding Top Freddie Mercury Fell in Love With," 30 Oct. 2018 The visit includes a private display of the museum's exquisite Peacock Clock in operation – something few people ever get to see. Gene Sloan, USA TODAY, "Exclusive events, all-inclusive fares: Inside the Tauck formula for small-ship cruising," 13 July 2018 More than 200 Ospreys — a tilt-rotor aircraft that can take off like a helicopter and fly like an airplane — are in operation with the U.S. military. Gordon Dickson, star-telegram, "Bell just got a big military aircraft contract. Will Fort Worth get any new jobs?," 12 July 2018 At the edge of the marina sits the Algoma Pierhead Lighthouse, a picturesque red lighthouse that was installed in 1932 to replace a square structure that had been in operation since 1892. Chelsey Lewis, Milwaukee Journal Sentinel, "Algoma is a day trip away along Lake Michigan," 12 July 2018 Adnan Raj, 31, was arrested as a part of an online predator sting operation, according to a news release. Claire Morgan, sacbee, "Meth, hard lemonade, condoms: Sacramento man arrested in online predator sting," 12 July 2018 The mission to rescue them is an extraordinary international operation with hundreds of cave and rescue experts and military personnel from several different countries, including the United States, pitching in. Radhika Viswanathan, Vox, "Why 12 Thai boys are still trapped in a cave, days after being found," 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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Statistics for operation

Last Updated

13 Nov 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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something that serves to warn or remind

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