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 After 35 years of operation, the Matador closed in 2012, reported with a hefty back tax bill. Douglas C. Towne, The Arizona Republic, "Schlitz beer and chop suey: Recalling the lost night-time hot spots of downtown Phoenix," 6 May 2021 But Straubel has early good news: after just one year of operation, Redwood Materials can already salvage tons of usable metals at costs below conventional mining. Alan Ohnsman, Forbes, "Tesla Tech Whiz Is Mining Riches From Your Old Batteries," 6 May 2021 Shuttle buses that run from a parking lot to the grove will be out of operation for the season, meaning tree lovers will have to hike four miles round trip to get to the sequoias. Gregory Thomas, San Francisco Chronicle, "Yosemite's Mariposa Grove reopens after brutal windstorm that toppled sequoias," 5 May 2021 Rock City Taco hours of operation are 7 a.m.-11 p.m. daily. Eric E. Harrison, Arkansas Online, "Rock City Taco opens in River Market in time for Cinco de Mayo," 5 May 2021 Signage bearing the name Miller Park was returned to the company, which purchased naming rights for the stadium's first 20 years of operation. Jr Radcliffe, Milwaukee Journal Sentinel, "There's still time to enter and win a bottle opener made from an old Miller Park sign," 4 May 2021 The market at University Place and Oak Avenue is now in its 46th year of operation. Karie Angell Luc, chicagotribune.com, "With safety measures in place, farmers market season kicks off on the North Shore," 4 May 2021 Westshaw also agreed to slowly pay the city another $6.3 million for habitat preservation during the first 12 years of operation, a period that ended Dec. 30. David Garrick, San Diego Union-Tribune, "San Diego sues Grand Del Mar resort for $1.5M in allegedly unpaid fees," 4 May 2021 The café's original hours of operation were from 7 a.m. to 8 p.m. David Reamer, Anchorage Daily News, "Here’s how an airport cafe specializing in pie grew into the Anchorage institution known as Peggy’s Restaurant," 2 May 2021

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

9 May 2021

Cite this Entry

“Operation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/operation. Accessed 12 May. 2021.

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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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