Operation (noun)

1. The process of working or doing something, especially using a particular set of tools or methods.
2. A business or organization, or a particular aspect of one.

Origin:

Late middle english: from old french, or from latin operatio(n-), from operari "work, labor".

Examples:

1. The operation of the machine was not understood by anyone.
2. The company is planning to expand its operations.
3. The operation was successful and the patient is recovering.
4. The police conducted a covert operation to catch the criminals.
5. The operation of the new software is quite simple.