operation

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noun

British English pronunciation: operation

/ˌɒpəˈreɪʃ(ə)n/

singular	operation
plural	operations

1
[countable] a planned activity involving a lot of people, especially soldiers or police officers
This was the biggest military operation for 20 years.
Undercover operations led to the arrest of the gang.
rescue/relief/cleanup operation:
The cleanup operation will take weeks.
Thesaurus entry for this meaning of operation
2
[countable] an action or set of actions that is necessary to achieve something
Connecting the water supply is a very simple operation.
The computer performs this operation many times every day.
Thesaurus entry for this meaning of operation
3
[countable] the process of cutting into someone's body for medical reasons
a stomach/heart operation
operation on:
She may need an operation on her knee.
have/undergo an operation:
The baby had to have an operation, but he's fine now.
do/perform/carry out an operation:
A very experienced heart surgeon will perform the operation.
Thesaurus entry for this meaning of operation
4
[countable] a company, or a part of a large company
The company has recently expanded its UK operation.
The group is selling its overseas operations.
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5
[uncountable] the way that something such as a system or service operates
We are visiting schools to explain the operation of the new exam system.
Thesaurus entry for this meaning of operation
1. a.
  used about the way that a machine or piece of equipment operates
  Something was interfering with the radar equipment's operation.
  Thesaurus entry for this meaning of operation
2. b.
  used about the way that something such as a rule or an idea is used
  Science investigates the operation of general laws.
  Thesaurus entry for this meaning of operation
6
[uncountable] the process of controlling something or of making it work
Operation of this equipment requires special training.
Thesaurus entry for this meaning of operation

phrases

in operation
1. 1
  working in the normal way
  How long has the business been in operation?
  Only one of our telephone lines is currently in operation.
  Thesaurus entry for this meaning of operation
2. 2
  existing and having an effect in a situation
  Guidelines governing the use of email are now in operation.
  Thesaurus entry for this meaning of operation
into operation
if something comes or goes into operation, it starts to work or become effective
The new production plant went into operation last month.
put/bring something into operation:
New legislation will be brought into operation in January.
Thesaurus entry for this meaning of operation

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