n. [ Trade name. ] 1. the collective trade name for a type of plastic food-storage container with a translucent bottom and a close-fitting lid designed to seal the container tightly. It is in common use in the late 20th century and early 21st century in the U. S. It comes in a variety of shapes and sizes, suitable for storing a variety of items. Also used attributively. She saved the leftovers in a couple of Tupperware containers. [ PJC ]