op·​er·​a·​tion | \ ˌä-pə-ˈrā-shən How to pronounce operation (audio) \

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 And his comments were echoed by president of baseball operations, Chris Antonetti. Joe Noga, cleveland, "Francisco Lindor, Chris Antonetti talk contract; Terry Francona talks outfield: Indians spring training podcast," 18 Feb. 2020 President of baseball operations David Stearns met afterward with Hader to assure there were no hard feelings and that both sides were ready to move on. Tom Haudricourt, Milwaukee Journal Sentinel, "Brewers closer Josh Hader lost his arbitration case, but he'll still get a $3.4 million raise," 14 Feb. 2020 As usual, this is an underfunded area in the budget, despite the importance (and cost-effectiveness) of such operations. James Stavridis, Time, "What the Trump Defense Budget Gets Wrong About the Future of War," 13 Feb. 2020 Department of Corrections emails obtained by The Associated Press show the agency's former deputy chief of operations reached out to a manufacturer of reduced oxygen breathing units used to help train pilots on the signs and symptoms of hypoxia. CBS News, "Oklahoma's attorney general says executions will resume after 5 year hold," 13 Feb. 2020 Taylor’s staff consists of 22 assistants and one director of coaching operations. Tyler Dragon, Cincinnati.com, "Cincinnati Bengals add assistant coaches Troy Walters and Colt Anderson to staff," 10 Feb. 2020 The day-to-day operations of these outlets are managed by our franchisee partner. Sangeeta Tanwar, Quartz India, "Delhi’s neighbourhood milk booth wants to switch it up with new cafes," 9 Feb. 2020 Yet the agreement gives New York City bureaucrats broad influence over the fashion house’s day-to-day operations, including its creative process, training and hiring. The Editorial Board, WSJ, "Prada and the New Fashion Police," 7 Feb. 2020 The new executives are Eric Bresler, who has been named senior vp of programming; Tom Conroy as vp of operations; and Rosemary Selle as vp of marketing. Chris Eggertsen, Billboard, "Executive Turntable: Ingrooves Opens Tokyo Office; Moves at Deezer, Oak View Group & RCA Nashville," 7 Feb. 2020

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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Time Traveler for operation

Time Traveler

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

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Statistics for operation

Last Updated

20 Feb 2020

Cite this Entry

“Operation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/operation. Accessed 28 Feb. 2020.

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More Definitions for operation


How to pronounce operation (audio)

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 How to pronounce operation (audio) \

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 How to pronounce operation (audio) \

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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