hour-glass

/AW1 ER0 G L AE0 S/
noun
  1. 1

    A clock made of two glass vessels connected by a narrow passage through which sand flows.

    โ€œAfter each game turn, invert the hourglass to reset the time limit for the next player.โ€

  2. 2

    A pointer, often shaped like an hourglass, indicating that the computer is busy.

Synonyms

Source: https://en.wiktionary.org/wiki/hour-glass, https://en.wiktionary.org/wiki/hourglass