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

Together, the company’s innovative offerings propelled LCS to its position today as an award-winning operation with over 280 employees and counting. Jessica Levy, Cincinnati.com, "For local employment opportunities, top tech professionals choose LCS," 7 June 2019 Smaller and lower-polluting operations would pay less, with 29% facing an increase of $1,000 a year or less, and another 39% seeing no increase at all, according to the air district. Tony Barboza, latimes.com, "Southern California’s most toxic polluters will pay more under air board’s fee hike," 7 June 2019 Sources tell Billboard that Paradigm’s relatively small film, TV and comedy divisions would benefit from integration into UTA’s stronger film and TV operation. Dave Brooks, Billboard, "UTA in Talks With Paradigm for Potential Merger," 7 June 2019 Ashiqul Alam, 22 years old, was arrested Thursday afternoon as the result of an elaborate law-enforcement surveillance operation. Corinne Ramey, WSJ, "Man Is Arrested Over Alleged Times Square Terror Plot," 7 June 2019 Villard, the attorney general, said the violence is worse now than in 2004, when former President Jean-Bertrand Aristide was toppled by a rebellion that led to the intervention by the U.N. peacekeeping force, whose operation will end in October. Fox News, "Leader or killer? A day with 'Barbecue' in Haiti's capital," 7 June 2019 The motor club cited a report that drivers across the state incur up to $633 in additional vehicle operation costs directly attributable to poor road conditions every year. Mary Wisniewski, chicagotribune.com, "From road repairs to transit expansions, $33 billion in capital bill will have ‘monumental’ impact," 7 June 2019 Phillips went through one surgery, and is expected to go through future operations, Ivey said. Joe Mario Pedersen, orlandosentinel.com, "Brevard deputy is recovering after Indialantic shooting, sheriff says," 7 June 2019 The water and sewer operation is an enterprise fund, meaning the city only charges users for costs. Steve Lord, Aurora Beacon-News, "Aurora aldermen set to vote on water and sewer rate hike," 7 June 2019

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

12 Jun 2019

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 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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