A clock made of two glass vessels connected by a narrow passage through which sand flows.
A cursor, often shaped like an hourglass, indicating that the computer is busy.
A sandglass.
An item of glass laboratory equipment consisting of a simple, slightly concave circle of glass. It is a general utility item, used to hold small samples, to evaporate liquids, to cover a beaker, and so on.
The glass covering of the face of a watch.