sandglass

A glass vessel consisting of two equal, nearly conical, and coaxial receptacles connected by a small opening at their vertices, one of which contains sand, which, if the glass is turned, runs through the opening into the other, the amount of sand being so regulated that a certain space of time is exactly measured by its running through. Compare hour-glass, minute-glass.

An instrument for measuring time by the running of sand. See hourglass.

An instrument for measuring the passage of time by the passage of sand through a narrow opening.

timepiece in which the passage of time is indicated by the flow of sand from one transparent container to another through a narrow passage