Other forms: slippers
A slipper is a kind of indoor shoe that slips easily on and off your foot. You may prefer to walk around barefoot unless it's really cold, in which case you wear slippers.
Slippers are cozy, and they're often warm too. A more old fashioned kind of slipper was a dress shoe that slipped on the foot, rather than being buckled or buttoned—like Cinderella's glass slipper. The word comes from the fact that you can slip a slipper on or off easily. It's related to the Old English slypescoh, literally "slip-shoe."