operation
Pluraloperations (some meanings)
- 1The way something such as a machine, system, or organization works or is run, or the fact of its working or being in use.
The smooth operation of the factory depends on regular maintenance.
Continuous operation of the pumps kept the mine free of water.
UsageOften in set phrases: a machine is in operation (working), and a law or plan comes into operation or is put into operation.
Note
Here the noun keeps an old, general weight, the working of a force. Locke writes of manna's operations on the stomach, and Dryden's du Fresnoy sets manual operation against speculative painting. The obsolete "effect" sense names the result; this one names the working itself.
- 2A business or organization, especially one viewed in terms of its activity and management.
Their manufacturing operation spans three countries.
She built the entire operation from a single storefront.
UsageYou run an operation, often named by what it does: a farming operation, a mining operation.
Similarbusiness, enterprise, company, concern
- 3A surgical procedure performed on a patient's body, usually to treat or diagnose injury, disease, or another condition.
The operation to repair her heart valve was a complete success.
Surgeons scheduled the operation for early the next morning.
UsageA patient has an operation and a surgeon performs one; the body part follows on: an operation on the knee.
Note
It has long been used for animals too. William Ellis's The Country Housewife's Family Companion (1750) describes a housewife performing the same operation on each side of a cock to make a capon, then stitching the wounds.
- 4A coordinated military campaign or mission carried out to achieve a specific objective.
The operation involved thousands of troops and weeks of planning.
Commanders called off the operation when the weather turned.
UsageIn a mission's name it comes first, capitalized, with no article: Operation Desert Storm. Otherwise it is lowercase: the operation.
- 5A planned undertaking carried out to achieve a specific objective, often involving coordinated effort.
The cleanup operation involved hundreds of volunteers and lasted a full week.
Police launched a major operation to track down the smugglers.
UsagePeople launch or carry out an operation, often named by its aim: a rescue operation, a cleanup operation.
Similareffort, undertaking, drive, exercise
- 6In mathematics and computing, a process or rule, such as addition or multiplication, that produces a value from one or more input values (operands).
Multiplication is an operation that combines two numbers into a product.
The program applies each operation to the data in sequence.
Note
Mathematics and computing classify an operation by how many inputs it takes. That number is its arity, so an operation taking two operands, such as addition, is a binary operation. Function and transformation overlap with it. Operation is the usual word when the emphasis falls on combining operands into a result, as with addition or multiplication.
Checked 5 Nov 2026 · 2 facts
- Operations in mathematics and computing are classified by their number of inputs, called arity. cs.yale.edu
- An operation taking two operands is binary; addition is an example. cs.yale.edu
Less common meaning
- 7The effect produced by some agent or force; the influence it exerts upon a subject.
Note
An obsolete use that names the result rather than the working: what a force does to whoever feels it. It took on or upon before its object, so Thomas Fuller in 1655 could write that the bards "had great operation on the vulgar," meaning great sway over ordinary people. Modern English keeps the act of exerting power but says effect or influence here, so reserve this use for echoing older prose.
Checked 5 Nov 2026 · 5 facts
- Operation historically meant an effect produced or an influence. en.wiktionary.org
- The historical influence sense occurred with upon before the affected subject. en.wikisource.org
- Thomas Fuller wrote the quoted words about bards, using on before the affected people. archive.org
- The work containing Fuller's quotation, The Church History of Britain, first appeared in 1655. en.wikisource.org
- The vulgar in the quotation means ordinary people. en.wiktionary.org
Practice
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Origin
From Middle English operacioun, borrowed via Old French operacion from Latin operātiō, which comes from the verb operor ("I work"), itself from opus, operis ("work"). It is equivalent to operate + -ion.
Checked 5 Nov 2026 · 5 facts
- English operation comes from Middle English operacioun through Old French operacion from Latin operātiō. en.wiktionary.org
- Latin operātiō derives from the verb operor. en.wiktionary.org
- Operor is the Latin verb form meaning I work. en.wiktionary.org
- The Latin ancestry ultimately leads to opus, genitive operis, meaning work. en.wiktionary.org
- Operation is morphologically equivalent to operate plus -ion. en.wiktionary.org