noun: the activity of operating something (a machine or business etc.)
Example: "Her smooth operation of the vehicle gave us a surprisingly comfortable ride"
noun: a planned activity involving many people performing various actions
Example: "They organized a rescue operation"
noun: a process or series of acts especially of a practical or mechanical nature involved in a particular form of work
Example: "The operations in building a house"
noun: a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body
Example: "They will schedule the operation as soon as an operating room is available"
noun: activity by a military or naval force (as a maneuver or campaign)
Example: "It was a joint operation of the navy and air force"
noun: a business especially one run on a large scale
Example: "A large-scale farming 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)
Example: "It can perform millions of operations per second"
noun: process or manner of functioning or operating
Example: "The power of its engine determine its operation"
noun: the state of being in effect or being operative
Example: "That rule is no longer in operation"
noun: (mathematics) calculation by mathematical methods
Example: "They were learning the basic operations of arithmetic"
noun: (psychology) the performance of some composite cognitive activity; an operation that affects mental contents