operation
noun
op·er·a·tion
ˌä-pə-ˈrā-shən 
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.
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
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.
6
a
: 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
Cite this Entry
“Operation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/operation. Accessed 4 Jun. 2025.
Copy CitationKids Definition
operation
noun
op·er·a·tion
ˌäp-ə-ˈrā-shən
1
: the act, process, method, or result of operating
does the whole operation without stopping
the operation of a drug
2
: the quality or state of being able to work or function
put a factory into operation
3
: a procedure performed on a living body usually with medical instruments especially to restore health or repair damage or defect
4
: a mathematical or logical process (as addition or multiplication) for getting one mathematical expression from others according to a rule
5
: the process of putting military or naval forces into action
6
: a single step in a computer program
7
: a usually small business or establishment
Medical Definition
operation
noun
op·er·a·tion
ˌäp-ə-ˈrā-shən
: a procedure performed on a living body usually with instruments for the repair of damage or the restoration of health and especially one that involves incision, excision, or suturing
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