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noun op·er·a·tion \ˌä-pə-ˈrā-shən\

Simple 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of operation

  1. 1 :  performance of a practical work or of something involving the practical application of principles or processes

  2. 2 a :  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. 3 :  efficacy, potency —archaic except in legal usage

  4. 4 :  a procedure performed on a living body usually with instruments especially for the repair of damage or the restoration of health

  5. 5 :  any of various mathematical or logical processes (as addition) of deriving one entity from others according to a rule

  6. 6 a :  a usually military action, mission, or maneuver including its planning and execution b 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 plural :  the agency of an organization charged with carrying on the principal planning and operating functions of a headquarters and its subordinate units

  7. 7 :  a business transaction especially when speculative

  8. 8 :  a single step performed by a computer in the execution of a program

  9. 9 :  a usually small business or establishment <ran a struggling operation>

Examples of operation in a sentence

  1. The family runs a small farming operation.

  2. The company is a billion-dollar operation.

Origin and Etymology of operation

Middle English operacioun, from Middle French operation, from Latin operation-, operatio, from operari

First Known Use: 14th century

Rhymes with operation

abdication, aberration, abjuration, abnegation, abrogation, acceptation, acclamation, accusation, activation, adaptation, adjuration, admiration, adoration, adulation, adumbration, affectation, affirmation, aggravation, aggregation, agitation, allegation, allocation, amputation, alteration, altercation, animation, annexation, annotation, appellation, application, approbation, arbitration, arrogation, aspiration, assignation, attestation, augmentation, automation, aviation, avocation, blaxploitation, botheration, calculation, calibration, cancellation, carbonation, castigation, celebration, cerebration, chlorination, circulation, cogitation, collocation, coloration, combination, comfort station, commendation, commutation, compensation, complication, computation, concentration, condemnation, condensation, confirmation, confiscation, conflagration, conformation, confrontation, congregation, conjugation, connotation, consecration, conservation, consolation, constellation, consternation, constipation, consultation, consummation, contemplation, conurbation, conversation, convocation, copulation, coronation, corporation, correlation, corrugation, crenellation, crop rotation, culmination, cultivation, cumulation, cybernation, decimation, declamation, declaration, declination, decoration, dedication, defamation, defecation, deformation, degradation, dehydration, delectation, delegation, demarcation, demonstration, denigration, denotation, depilation, deportation, depravation, depredation, deputation, derivation, derogation, desecration, designation, desolation, desperation, destination, detestation, detonation, devastation, deviation, dislocation, dispensation, disputation, dissertation, dissipation, distillation, divination, domination, education, elevation, elongation, emanation, embarkation, embrocation, emendation, emigration, emulation, enervation, escalation, estimation, evocation, exaltation, excavation, excitation, exclamation, exculpation, execration, exhalation, exhortation, exhumation, expectation, expiation, expiration, explanation, explication, exploitation, exploration, exportation, expurgation, extirpation, exultation, fabrication, fascination, federation, fenestration, fermentation, fibrillation, figuration, filling station, fire station, flagellation, fluoridation, fluctuation, forestation, formulation, fornication, fragmentation, fulmination, fumigation, gene mutation, generation, germination, glaciation, graduation, granulation, gravitation, habitation, hesitation, hibernation, hyphenation, ideation, imitation, immigration, immolation, implantation, implication, importation, imprecation, imputation, incantation, incarnation, inclination, incrustation, incubation, indentation, indication, indignation, infestation, infiltration, inflammation, information, inhalation, innovation, inspiration, installation, instigation, insulation, integration, intimation, intonation, inundation, invitation, invocation, irrigation, irritation, iteration, jubilation, laceration, lamentation, lamination, legislation, levitation, liberation, limitation, lineation, liquidation, litigation, lubrication, lucubration, maceration, machination, malformation, masturbation, maturation, mediation, medication, meditation, melioration, menstruation, ministration, mitigation, moderation, modulation, molestation, motivation, mutilation, navigation, nomination, obfuscation, objurgation, obligation, observation, occupation, orchestration, ordination, oscillation, osculation, ostentation, ovulation, oxidation, pagination, palpitation, penetration, percolation, perforation, permeation, permutation, perpetration, perspiration, perturbation, pigmentation, pixilation, police station, pollination, population, postulation, power station, predication, preparation, presentation, preservation, proclamation, procreation, profanation, prolongation, promulgation, propagation, prorogation, protestation, provocation, publication, punctuation, radiation, recantation, recitation, reclamation, re-creation, recreation, reformation, refutation, registration, regulation, rehydration, relaxation, relocation, renovation, reparation, replication, reprobation, reputation, reservation, resignation, respiration, restoration, retardation, revelation, revocation, ruination, rumination, rustication, salutation, sanitation, saturation, segmentation, segregation, separation, sequestration, service station, sexploitation, simulation, situation, speciation, speculation, spoliation, stimulation, stipulation, strangulation, structuration, stylization, subjugation, sublimation, suffocation, syncopation, syndication, tabulation, termination, T formation, titillation, toleration, transfer station, transformation, translocation, transmigration, transmutation, transpiration, transplantation, transportation, trepidation, tribulation, ulceration, ululation, undulation, urination, vaccination, vacillation, validation, valuation, variation, vegetation, veneration, ventilation, vindication, violation, visitation, weather station

OPERATION Defined for Kids


noun op·er·a·tion \ˌä-pə-ˈrā-shən\

Definition of operation for Students

  1. 1 :  a set of actions for a particular purpose <a rescue operation>

  2. 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. 3 :  the process of putting military forces into action <naval operations>

  4. 4 :  the state of working or being able to work <The factory is now in operation.>

  5. 5 :  a method or manner of working <The camera is designed for easy operation.>

  6. 6 :  a process (as addition or multiplication) of getting one mathematical expression from others according to a rule

  7. 7 :  a single step performed by a computer in carrying out a program

Medical Dictionary


noun op·er·a·tion \ˌäp-ə-ˈrā-shən\

Medical Definition of operation

  1. :  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

Seen and Heard

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to take off or remove

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