Cleaning processor was a piece of technology on Starfleet vessels, used to clean pieces of clothing.
While in Ten Forward on the USS Enterprise-D in 2367, Keiko O'Brien recounted to Lieutenant Commander Data and Lieutenant Jenna D'Sora that after she and her husband Miles had gotten married, Miles kept leaving his socks on the floor of their quarters. Eventually, they began to pile up. Keiko had enough and threw them into the cleaning processor. (TNG: "In Theory")