![Dixon Hill cleaning lady](https://cdn.statically.io/img/static.wikia.nocookie.net/memoryalpha/images/6/64/Dixon_Hill_cleaning_lady.jpg/revision/latest/scale-to-width-down/180?cb=20120819032004&path-prefix=en)
The cleaning lady with the mop
A mop was a tool used to clean up spilled liquids or dust from a flat surface such as a floor.
In 2364, upon entering the Dixon Hill holoprogram, Jean-Luc Picard encountered a woman mopping the floor just outside the private investigator's office. (TNG: "The Big Goodbye")