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aether

[ee-ther] /ˈi θər/
noun
1.
ether (defs 3–5).
2.
(initial capital letter) the ancient Greek personification of the clear upper air of the sky.
Related forms
aethereal
[ih-theer-ee-uh l] /ɪˈθɪər i əl/ (Show IPA),
aetheric
[ih-ther-ik] /ɪˈθɛr ɪk/ (Show IPA),
adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for aether's

aether

/ˈiːθə/
noun
1.
a variant spelling of ether (sense 3), ether (sense 4), ether (sense 5)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Encyclopedia Article for aether's

aether

in physics, a theoretical, universal substance believed during the 19th century to act as the medium for transmission of electromagnetic waves (e.g., light and X rays) much as sound waves are transmitted by elastic media such as air. The ether was assumed to be weightless, transparent, frictionless, undetectable chemically or physically, and literally permeating all matter and space. The theory met with increasing difficulties as the nature of light and the structure of matter became better understood; it was seriously weakened (1881) by the Michelson-Morley experiment (q.v.), which was designed specifically to detect the motion of the Earth through the ether and which showed that there was no such effect

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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9
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