Princeton's WordNet

1. operation(noun)

   the state of being in effect or being operative

   "that rule is no longer in operation"

2. operation(noun)

   a business especially one run on a large scale

   "a large-scale farming operation"; "a multinational operation"; "they paid taxes on every stage of the operation"; "they had to consolidate their operations"

3. operation(noun)

   a planned activity involving many people performing various actions

   "they organized a rescue operation"; "the biggest police operation in French history"; "running a restaurant is quite an operation"; "consolidate the companies various operations"

4. operation(noun)

   (computer science) data processing in which the result is completely specified by a rule (especially the processing that results from a single instruction)

   "it can perform millions of operations per second"

5. operation, military operation(noun)

   activity by a military or naval force (as a maneuver or campaign)

   "it was a joint operation of the navy and air force"

6. operation, surgery, surgical operation, surgical procedure, surgical process(noun)

   a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body

   "they will schedule the operation as soon as an operating room is available"; "he died while undergoing surgery"

7. operation, procedure(noun)

   a process or series of acts especially of a practical or mechanical nature involved in a particular form of work

   "the operations in building a house"; "certain machine tool operations"

8. operation, functioning, performance(noun)

   process or manner of functioning or operating

   "the power of its engine determines its operation"; "the plane's operation in high winds"; "they compared the cooking performance of each oven"; "the jet's performance conformed to high standards"

9. process, cognitive process, mental process, operation, cognitive operation(noun)

   (psychology) the performance of some composite cognitive activity; an operation that affects mental contents

   "the process of thinking"; "the cognitive operation of remembering"

10. mathematical process, mathematical operation, operation(noun)

    (mathematics) calculation by mathematical methods

    "the problems at the end of the chapter demonstrated the mathematical processes involved in the derivation"; "they were learning the basic operations of arithmetic"

11. operation(noun)

    the activity of operating something (a machine or business etc.)

    "her smooth operation of the vehicle gave us a surprisingly comfortable ride"

Kernerman English Learner's Dictionary

1. operation(noun)ˌɒp əˈreɪ ʃən

   the process of operating on sb's body

   a routine operation on her foot; When are you having your operation?

2. operationˌɒp əˈreɪ ʃən

   a planned activity intended to achieve a particular result

   a military operation; mining operations in Australia; Our business operations may have an impact on the local community.

3. operationˌɒp əˈreɪ ʃən

   the way sth works or is used

   Operation of the robot is by remote control.

4. operationˌɒp əˈreɪ ʃən

   working or in use

   The new system should be in operation by next year.

Wiktionary

1. operation(Noun)

   The method by which a device performs its function.

   It is dangerous to look at the beam of a laser while it is in operation.

2. operation(Noun)

   The method or practice by which actions are done.

3. operation(Noun)

   A planned undertaking.

4. operation(Noun)

   A business or organization.

5. operation(Noun)

   a surgical procedure.

   She had an operation to remove her appendix.

6. operation(Noun)

   a procedure for generating a value from one or more other values (the operands; the value for any particular operands is unique)

7. operation(Noun)

   a military campaign (w:Operation Desert Storm)

Origin: From operari, from opus, operis

Dictionary of Military and Associated Terms

1. operation

   1. A military action or the carrying out of a strategic, operational, tactical, service, training, or administrative military mission. 2. The process of carrying on combat, including movement, supply, attack, defense, and maneuvers needed to gain the objectives of any battle or campaign.

• operasieAfrikaans
• عَمَلِيَّهArabic
• операцияBulgarian
• operaçãoPortuguese (BR)
• operaceCzech
• das UnternehmenGerman
• operation; -operationDanish
• επιχείρηση, διαδικασίαGreek
• operaciónSpanish
• operatsioonEstonian
• کار؛ عملکردFarsi
• toimenpideFinnish
• opérationFrench
• מִבצָעHebrew
• अभियानHindi
• operacijaCroatian
• műveletHungarian
• operasiIndonesian
• aðgerðIcelandic
• operazioneItalian
• 作業Japanese
• 작업Korean
• operacijaLithuanian
• operācijaLatvian
• operasiMalay
• actieDutch
• operasjon, virksomhet, prosessNorwegian
• operacjaPolish
• کار؛ عملکردPersian
• عملياتPashto
• operaçãoPortuguese
• ope­ra­ţiuneRomanian
• операцияRussian
• operáciaSlovak
• akcijaSlovenian
• operacijaSerbian
• operation, företagSwedish
• การดำเนินการThai
• operasyon, harekâtTurkish
• 操作，作業Chinese (Trad.)
• операціяUkrainian
• کام، عملUrdu
• sự hoạt độngVietnamese
• 操作，工作Chinese (Simp.)