hourglass Meaning, Definition & Usage

Hour"glass` noun

Definitions

1. An instrument for measuring time, especially the interval of an hour. It consists of a glass vessel having two compartments, from the uppermost of which a quantity of sand, water, or mercury occupies an hour in running through a small aperture unto the lower. ✍ A similar instrument measuring any other interval of time takes its name from the interval measured; as, a half-hour glass, a half-minute glass. A three-minute glass is sometimes called an egg-glass, from being used to time the boiling of eggs. also = egg timer