Definition of operation
1 : performance of a practical work or of something involving the practical application of principles or processes Practice until you can go through the whole operation without hesitation or thinking.
2a : 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
4 : a procedure performed on a living body usually with instruments especially for the repair of damage or defect or the restoration of health needed an operation to remove his appendix
5 : any of various mathematical or logical processes (such as addition) of deriving one entity from others according to a rule Multiplication is one mathematical operation.
6a : a usually military action, mission, or maneuver including its planning and execution military operations for a large-scale invasion
b operations 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 operations plural : the agency of an organization charged with carrying on the principal planning and operating functions of a headquarters and its subordinate units
7 : a business transaction especially when speculative continued his operations in cotton futures
8 : a single step performed by a computer in the execution of a program (see program entry 1 sense 6a)
9 : a usually small business or establishment ran a struggling operation
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