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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"
(psychology) the performance of some composite cognitive activity; an operation that affects mental contents; "the process of thinking"; "the cognitive operation of remembering"
(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"
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"
the state of being in effect or being operative; "that rule is no longer in operation"