sandglass

/ˈsændɡlæs/
noun
  1. A device for measuring time, consisting of two glass bulbs connected by a narrow neck, through which sand flows from the upper to the lower bulb.
    • In the old library, a large sandglass sat on the desk to remind visitors of the passing hours.
    • The chef used a sandglass to time the perfect three-minute egg.
    • She turned the sandglass over and watched the fine grains trickle down.
Synonyms
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