Sippy cup
The sippy cup, training cup, or beaker is a drinking cup designed for toddlers which prevents or reduces spills. Sippy cups, as opposed to an open cup, have a top which prevents spills, and the child drinks either through a spout or straw. Some sippy cups work by way of surface tension that prevents liquid from being spilled even when the cup is upended, and others have valves. A sippy cup is typically an intermediary between the transition between the bottle or breast to an open cup; however, some recommend skipping the sippy cup and transitioning directly to an open cup.
The Sipster spill-proof sippy cup was invented by Richard Belanger, who licensed the design to Playtex.