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operation

n.
US //ˌɑpɝˈeɪʃən// UK //ˌɒpəɹˈeɪʃən// op·er·a·tion
  1. 1 medical surgery (n.)
    B1 Intermediate Medicine

    a medical procedure where a doctor cuts into a person's body to fix or remove something.

    a surgical procedure performed by medical professionals to treat a pathological condition or injury.

    Example

    He had a minor operation on his knee to repair the damaged tissue.

    Example

    The patient underwent a complex five-hour operation to remove the tumor, followed by several weeks of intensive recovery.
  2. 2 business or activity (n.)
    B2 Upper Intermediate

    the way a business or organization works and does its daily activities.

    the functional activities or management of a business, organization, or system.

    Example

    The company is moving its main operation to a larger office in the city.

    Example

    The logistics operation requires precise coordination between the warehouse staff and the international shipping department.
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  1. 3 military/police plan (n.)
    B2 Upper Intermediate Military

    a planned action by the military or police to achieve a specific goal.

    a coordinated set of actions by military or police forces designed to achieve a strategic objective.

    Example

    The police launched a secret operation to catch the thieves.

    Example

    The joint military operation was executed with surgical precision, successfully securing the border without any civilian casualties.
  2. 4 functioning of a machine (n.)
    B1 Intermediate Technical

    the way a machine or system works when it is turned on.

    the state of being functional or the specific manner in which a device performs its intended task.

    Example

    The manual explains the safe operation of the heating system.

    Example

    The engineers monitored the operation of the turbine throughout the night to ensure the vibrations remained within safety limits.
  3. 5 math/logic process (n.)
    B2 Upper Intermediate Academic Math

    a mathematical process like adding or subtracting numbers.

    a mathematical or logical procedure that takes one or more input values to produce a defined output.

    Example

    Addition is the first mathematical operation that children learn in school.

    Example

    The algorithm performs a complex logical operation on the data set before generating the final report.
Origin

Etymology tree Proto-Indo-European *h₃ep- Proto-Indo-European *-os Proto-Indo-European *h₃épos Proto-Italic *opos Latin opus Latin opera Proto-Indo-European *-h₂ Proto-Indo-European *-éh₂ Proto-Indo-European *-tós Proto-Indo-European *-eh₂tos Proto-Italic *-ātos Latin -ātus Latin operātus Latin operor Proto-Indo-European *-tisder. Proto-Italic *-tjō Latin -tiō Latin operātiōder. Old French operacionbor. Middle English operacioun English operation From Middle English operacioun, from Old French operacion, from Latin operātiō, from the verb operor (“to work”), from opus, operis (“work”). Equivalent to operate + -ion.

Idioms1 entry

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