Main Entry: op·er·a·tion

Pronunciation: \ˌä-pə-ˈrā-shən\

Function: noun

Etymology: Middle English operacioun, from Middle French operation, from Latin operation-, operatio, from operari

Date: 14th century

1 : performance of a practical work or of something involving the practical application of principles or processes
2 a : 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>
3 : efficacy, potency —archaic except in legal usage
4 : a procedure performed on a living body usually with instruments especially for the repair of damage or the restoration of health
5 : any of various mathematical or logical processes (as addition) of deriving one entity from others according to a rule
6 a : a usually military action, mission, or maneuver including its planning and execution b 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 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
8 : a single step performed by a computer in the execution of a program
9 : a usually small business or establishment <ran a struggling operation>