operation

The word “operation” means the way something works, or the act of making it work. In plain terms, a task, procedure, or process being carried out, whether it's a business plan, a military mission, a surgery, or a math step.

“Operation” is pronounced op-uh-RAY-shuhn (/ˌɑ.pəˈɹeɪ.ʃən/ in IPA).

Here is “operation” used in a sentence: “The operation of the new machine is simpler than expected.”

“Operation” is a noun.

The word “operation” comes from Latin. From Latin operatio, "a working," from the verb operari — the same root as "operate.".

“Operation” is a very common word in modern English, usually learned at around the B1 level.

“Operation” has 4 distinct senses listed in this dictionary. The most common is: the way something works, or the act of making it work.

An operation is the working or running of something — the act of making it work and the way it does so. A function is the purpose it serves or the job it's meant to do. A machine's function is what it's for; its operation is how it actually runs in practice.

Beyond the working or running of something, 'operation' has several senses: a surgical procedure ('a knee operation'), a planned military or organised effort ('a rescue operation'), a mathematical process like addition, and a business's activities ('overseas operations'). Context shows which meaning applies.

'In operation' means up and running, active, and doing its job. A factory in operation is producing goods; a rule in operation is currently in force. The phrase describes something that is not just switched on but actually functioning as intended at that time.

'The operation of the machine is simple' describes how it works. 'Staff explained the safe operation of the lift' refers to making it work correctly. Both use 'operation' in its core sense — the running of something — rather than the surgical or military meanings the word can also carry.