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Related to clepsydras: water clock


n. pl. clep·sy·dras or clep·sy·drae (-drē′)
An ancient device that measured time by marking the regulated flow of water through a small opening. Also called water glass.

[Latin, from Greek klepsudrā : kleptein, kleps-, to steal + hudōr, water; see wed- in Indo-European roots.]


n, pl -dras or -drae (-ˌdriː)
(Horology) an ancient device for measuring time by the flow of water or mercury through a small aperture. Also called: water clock
[C17: from Latin, from Greek klepsudra, from kleptein to steal + hudōr water]


(ˈklɛp sɪ drə)

n., pl. -dras, -drae (-ˌdri)
[1640–50; < Latin < Greek klepsýdra <kléptein to steal + hýdōr water]


an instrument for measuring time by the controlled flow of water or mercury through a small opening.
See also: Instruments, Time
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.clepsydra - clock that measures time by the escape of waterclepsydra - clock that measures time by the escape of water
clock - a timepiece that shows the time of day
References in periodicals archive ?
This resulted in the famous clepsydras or "water clocks," featuring vessels with a small hole in them, in which the level of the liquid made it possible to read off the time on a graduated vertical scale.
Water clocks, or clepsydras, let water drip out of (or into) a vessel at a nearly constant rate.
Instruments of astronomy in the subcontinent in medieval times, even in the reigns of rulers with an interest in this science--as for instance the 14th-century Tughlak ruler Firoz Shah at Delhi--essentially appear to consist of astrolabes, sundials and possibly clepsydras for telling the time.