A cleaner or a cleaning operative is a type of industrial or domestic worker who does the cleaning.

Cleaner in Cambridge English dictionary means: "a person whose job is to clean houses, offices, public places, etc.:", in Collins dictionary: "A cleaner is someone who is employed to clean the rooms and furniture inside a building." However, a cleaner does not always have to be employed and does not have to perform work for pay an example would be socially and charity cleaning for example free forest cleanup from garbage so the definitions of the cleaner word depend on the author. Word cleaner also means: "substance used for cleaning" e.g. oven cleaner and device used to clean e.g. an air cleaner.

To sum up, the simplest thing to say is that a cleaner is usually a person who does cleaning.

Cleaning operatives may specialize in cleaning particular things or places, such as window cleaners. Cleaning operatives often work when the people who otherwise occupy the space are not around. They may clean offices at night or houses during the workday.