operation

operation — noun

1. a medical procedure in which a doctor cuts into the body to remove, repair, or r

1.名詞B1
釋義

a medical procedure in which a doctor cuts into the body to remove, repair, or replace a part that is damaged or unhealthy.

例句

Lena had an operation on her knee after the skiing fall.

pattern: operation on [body part]

The child needed an emergency operation to stop the bleeding.

collocation: emergency operation

同義詞
  • surgery

    very close in meaning; also names the medical field more broadly

  • procedure

    broader and can include treatments that do not involve cutting

  • treatment

    much wider; medicine and therapy are treatments too

文法句型

have an operation

operation on [body part]

用法筆記

Most often follows have, need, undergo, or perform, and is often followed by 'on' plus the body part. In everyday use, patients have an operation and doctors perform one.

常見錯誤

I will do an operation tomorrow.
I will have an operation tomorrow.
💡Patients have operations; doctors do or perform them.

2. the condition of working and ready to be used, or of having legal effect at that

2.名詞C1
釋義

the condition of working and ready to be used, or of having legal effect at that time.

例句

By six o'clock, the bakery ovens were in operation again.

fixed phrase: in operation

The new safety rule comes into operation next Monday.

fixed phrase: come into operation

同義詞
  • effect

    used for laws and rules rather than machines or services

  • service

    used when a transport or public system is available for use

  • activity

    broader and less tied to working equipment or legal force

反義詞
  • shutdown

    the state of being stopped and not working

文法句型

in operation

come into operation

用法筆記

Often follows be, remain, or come into. Common with machines, services, and rules rather than with people.

常見錯誤

The rule will operate next Monday.
The rule will come into operation next Monday.
💡With laws and rules, this noun sense often appears in the fixed phrase 'come into operation'.

3. how a machine or system works, including the way its parts act together and the

3.名詞C1
釋義

how a machine or system works, including the way its parts act together and the way it is used correctly.

例句

The manual explains the operation of the heating system in clear steps.

pattern: operation of [system]

A short class taught new nurses the safe operation of the pump.

collocation: safe operation

同義詞
  • functioning

    focuses on the way something works, not on a person controlling it

  • working

    more everyday, but less precise in technical writing

  • handling

    focuses more narrowly on the user's control of equipment

文法句型

operation of [machine/system]

safe operation

smooth operation

用法筆記

Most often appears in 'operation of' phrases with machines, systems, and equipment. Distinguish from sense 2: this sense focuses on how something works or is handled, not simply whether it is active.

常見錯誤

The guide explains how to operation the printer.
The guide explains the operation of the printer.
💡Use the noun with 'the operation of', or use the verb 'operate'.

4. a carefully organized action involving several people, often by the military, po

4.名詞C1
釋義

a carefully organized action involving several people, often by the military, police, or rescue teams, to achieve a clear goal.

例句

Coast guards began a rescue operation after the fishing boat sank.

collocation: rescue operation

Police planned a dawn operation to catch the robbery gang.

pattern: operation to + verb

同義詞
  • mission

    close in meaning, often stressing the assigned goal

  • campaign

    usually longer and made up of several actions

  • raid

    narrower; a sudden police or military action

文法句型

rescue operation

operation to + verb

用法筆記

Common with a noun before it showing purpose, such as rescue, search, or military. Distinguish from sense 1: both may be planned, but this sense is a wider group action rather than treatment on a body.

常見錯誤

The school had an operation to clean one classroom.
The school organized a clean-up.
💡'Operation' usually sounds more natural for formal, official, or large-scale actions.

5. the day-to-day work of running a company or part of an industry, especially the

5.名詞C1
釋義

the day-to-day work of running a company or part of an industry, especially the practical side.

例句

After the flood, airport operations returned to normal by evening.

often plural: operations

The company moved its European operations to Dublin last year.

business use: regional operations

同義詞
  • running

    informal and broad; focuses on keeping something going

  • management

    focuses more on control and decision-making than practical work

  • logistics

    narrower; focuses on movement, supply, and organization

反義詞
  • shutdown

    a stop in business or industrial activity

文法句型

operations in [region]

airport operations

用法筆記

Very often used in the plural, especially for company departments, airports, factories, and regional business work. Distinguish from sense 7: this sense is the running work itself, not the business as a single organization.

常見錯誤

She works in operations of the company.
She works in the company's operations department.
💡This sense often appears in set business phrases such as 'operations department' and 'regional operations'.

6. a rule-based calculation such as addition or division that turns one number or q

6.名詞B2
釋義

a rule-based calculation such as addition or division that turns one number or quantity into another.

例句

Addition is the first operation children learn at school.

basic mathematical operation

The app performs the same operation on every number in Mia's table.

pattern: operation on [number]

同義詞
  • calculation

    broader everyday word for working out numbers

  • process

    broader and not limited to mathematics

  • function

    more technical and used for special mathematical relations

文法句型

mathematical operation

operation on [number]

用法筆記

Usually used when people name, choose, or repeat a calculation rule. Distinguish from sense 3: this sense is about numbers and formulas, not the working of a machine or system.

常見錯誤

The answer is the operation.
The answer comes from the operation.
💡The operation is the process, not the final result.

7. a business considered as the people, work, and systems that keep it running.

7.名詞C1
釋義

a business considered as the people, work, and systems that keep it running.

例句

The brothers turned their food truck into a larger operation.

grow a small business into an operation

What began in one garage is now a global software operation.

同義詞
  • business

    the broad everyday word

  • company

    a standard neutral term, often more formal than 'operation'

  • enterprise

    more formal and often used for larger or ambitious businesses

文法句型

run an operation

a small operation

用法筆記

Often used for a business that feels practical, busy, or somewhat informal in tone. Distinguish from sense 5: this sense names the business itself, while sense 5 is the work of running it.

常見錯誤

She works in a flower operation.
She works for a flower-growing operation.
💡When you mean the business as an employer, 'work for' is the natural choice.