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[ee-ol-uh-pahyl] /iˈɒl əˌpaɪl/
a round vessel caused to rotate by the force of tangentially escaping steam: an early example of jet propulsion.
a device for injecting the vapors of heated alcohol into a laboratory furnace.
Also, aeolipyle, eolipile.
1650-60; < Latin aeolīpilae balls of Aeolus, alteration of aeolīpylae gates of Aeolus, equivalent to Aeolī (genitive singular of Aeolus) + pylae, plural of pyla < Greek pýlē gate Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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British Dictionary definitions for aeolipyle


a device illustrating the reactive forces of a gas jet: usually a spherical vessel mounted so as to rotate and equipped with angled exit pipes from which steam within it escapes
Word Origin
C17: from Latin aeolīpilae balls of Aeolus or aeolīpylae gates of Aeolus
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Encyclopedia Article for aeolipyle


steam turbine invented in the 1st century AD by Heron of Alexandria and described in his Pneumatica. The aeolipile was a hollow sphere mounted so that it could turn on a pair of hollow tubes that provided steam to the sphere from a cauldron. The steam escaped from the sphere from one or more bent tubes projecting from its equator, causing the sphere to revolve. The aeolipile is the first known device to transform steam into rotary motion. Like many other machines of the time that demonstrated basic mechanical principles, it was simply regarded as a curiosity or a toy and was not used for any practical purpose.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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