1. the amount that a tumbler (drinking glass) can hold

Examples

• She drank a tumblerful of water after her workout.
• The recipe calls for a tumblerful of milk.
• He poured himself a tumblerful of orange juice.
• Add a tumblerful of broth to the mixture.
• The child finished a whole tumblerful of chocolate milk.
• Mix in a tumblerful of cold water gradually.