noun (n)

• the state of being in effect or being operative(noun.state)

  Example:
  That rule is no longer in operation.
  

  source: wordnet30
• a business especially one run on a large scale(noun.act)

  Example:
  A large-scale farming operation.
  A multinational operation.
  They paid taxes on every stage of the operation.
  They had to consolidate their operations.
  

  source: wordnet30
• a planned activity involving many people performing various actions(noun.act)

  Example:
  They organized a rescue operation.
  The biggest police operation in French history.
  Running a restaurant is quite an operation.
  Consolidate the companies various operations.
  

  source: wordnet30
• (computer science) data processing in which the result is completely specified by a rule (especially the processing that results from a single instruction)(noun.process)

  Example:
  It can perform millions of operations per second.
  

  source: wordnet30
• activity by a military or naval force (as a maneuver or campaign)(noun.act)

  Example:
  It was a joint operation of the navy and air force.
  

  Synonym:
  military operation
  

  source: wordnet30
• a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body(noun.act)

  Example:
  They will schedule the operation as soon as an operating room is available.
  

  Synonym:
  surgery, surgical operation, surgical procedure, surgical process
  

  source: wordnet30
• a process or series of acts especially of a practical or mechanical nature involved in a particular form of work(noun.act)

  Example:
  The operations in building a house.
  Certain machine tool operations.
  

  Synonym:
  procedure
  

  source: wordnet30
• process or manner of functioning or operating(noun.process)

  Example:
  The power of its engine determines its operation.
  The plane's operation in high winds.
  

  Synonym:
  functioning, performance
  

  source: wordnet30
• (psychology) the performance of some composite cognitive activity; an operation that affects mental contents(noun.cognition)

  Example:
  The cognitive operation of remembering.
  

  Synonym:
  cognitive operation, cognitive process, mental process, process
  

  source: wordnet30
• (mathematics) calculation by mathematical methods(noun.act)

  Example:
  They were learning the basic operations of arithmetic.
  

  Synonym:
  mathematical operation, mathematical process
  

  source: wordnet30
• the activity of operating something (a machine or business etc.)(noun.act)

  Example:
  Her smooth operation of the vehicle gave us a surprisingly comfortable ride.
  

  source: wordnet30
• The act or process of operating; agency; the exertion of power, physical, mechanical, or moral.(noun)

  source: webster1913