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

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 Independent has tapped former Voltage Pictures executive Marc Hofstatter to run the L.A. operation, which marks the first time the company has had a dedicated U.S. presence. K.j. Yossman, Variety, 5 May 2022 Healthcare research is a pan-global operation, one that spans private and public sectors and across borders. Tim Guilliams, Forbes, 5 May 2022 An increase in criminal activity in southwest Bexar County led to the discovery of what appears to be a smuggling operation involving about 40 migrants Thursday afternoon in Atascosa. Dennis Rudner, San Antonio Express-News, 5 May 2022 How to clean your earbuds Ridding your earbuds of gunk and germs is a three-fold operation. Terry Baddoo, USA TODAY, 2 May 2022 The driver was transported to the Cleveland Clinic in Avon and later charged with OVI, reckless operation, and failure to control. Cheryl Higley, cleveland, 30 Apr. 2022 The temporary operation, hosted in a Lutheran church in Northern Virginia, is led by the Lutheran Immigration and Refugee Services, or LIRS. Grace Segers, The New Republic, 27 Apr. 2022 Police say Spain is the main supplier of drugs to the operation, which spanned from Caroline and Dorchester counties to Anne Arundel and Prince George’s counties, along with parts of Delaware and the mid-Atlantic. Lilly Price, Baltimore Sun, 26 Apr. 2022 The Texas National Guardsman was at the border as part of Governor Abbott’s operation to secure the border — because the feds have failed to do so. Carine Hajjar, National Review, 26 Apr. 2022 See More

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.

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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Dictionary Entries Near operation

operating theatre



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Last Updated

9 May 2022

Cite this Entry

“Operation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/operation. Accessed 19 May. 2022.

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More Definitions for operation


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

More from Merriam-Webster on operation

Nglish: Translation of operation for Spanish Speakers

Britannica English: Translation of operation for Arabic Speakers

Britannica.com: Encyclopedia article about operation


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