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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Merriam-Webster unabridged
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Time Traveler for operation
The first known use of operation was in the 14th century
See more words from the same century