from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Any of a class of organic compounds in which two hydrocarbon groups are linked by an oxygen atom.
- n. A volatile, highly flammable liquid, C2H5OC2H5, derived from the distillation of ethyl alcohol with sulfuric acid and used as a reagent and solvent. It was formerly used as an anesthetic. Also called diethyl ether, ethyl ether.
- n. The regions of space beyond the earth's atmosphere; the heavens.
- n. The element believed in ancient and medieval civilizations to fill all space above the sphere of the moon and to compose the stars and planets.
- n. Physics An all-pervading, infinitely elastic, massless medium formerly postulated as the medium of propagation of electromagnetic waves.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A compound containing an oxygen atom bonded to two hydrocarbon groups.
- n. Diethyl ether (C4H10O), a compound used as an early anaesthetic.
- n. A classical physical element, considered as prevalent in the heavens and inaccessible to humans. In some versions of alchemy, this was the fifth element in addition to air, earth, fire and water.
- n. A substance (aether) once thought to fill all space that allowed electromagnetic waves to pass through it and interact with matter, without exerting any resistance to matter or energy (disproved by Einstein in his Theory of Relativity).
- n. The sky or heavens; the upper air.
from the GNU version of the Collaborative International Dictionary of English
- n. A medium of great elasticity and extreme tenuity, once supposed to pervade all space, the interior of solid bodies not excepted, and to be the medium of transmission of light and heat; hence often called luminiferous ether. It is no longer believed that such a medium is required for the transmission of electromagnetic waves; the modern use of the term is mostly a figurative term for empty space, or for literary effect, and not intended to imply the actual existence of a physical medium. However. modern cosmological theories based on quantum field theory do not rule out the possibility that the inherent energy of the vacuum is greater than zero, in which case the concept of an ether pervading the vacuum may have more than metaphoric meaning.
- n. Supposed matter above the air; the air itself.
- n. A light, volatile, mobile, inflammable liquid, (C2H5)2O, of a characteristic aromatic odor, obtained by the distillation of alcohol with sulphuric acid, and hence called also sulphuric ether. It is a powerful solvent of fats, resins, and pyroxylin, but finds its chief use as an anæsthetic. Commonly called ethyl ether to distinguish it from other ethers, and also ethyl oxide.
- n. Any similar compound in which an oxygen atom is bound to two different carbon atoms, each of which is part of an organic radical
from The Century Dictionary and Cyclopedia
- n. The upper air; the blue heavens. It was supposed by Aristotle to extend from the fixed stars down to the moon.
- n. In astronomy and physics, a hypothetical medium of extreme tenuity and elasticity supposed to be diffused throughout all space (as well as among the molecules of which solid bodies are composed), and to be the medium of the transmission of light and heat. See the extract.
- n. In chem.: One of a class of organic bodies divided into two groups: Simple ethers, consisting of two basic hydrocarbon radicals united by oxygen, and corresponding in constitution to the metallic oxids, as CH3OCH3, methylether, or methyloxid, analogous to AgOAg, silver oxid. Compound ethers, consisting of one or more basic or alcohol radicals and one or more acid hydrocarbon radicals united by oxygen, and corresponding to salts of the metals, as CH3COO C2H5, ethyl acetate, or acetic ether, corresponding to CH3COONa, sodium acetate. Also called esters
- n. Specifically, ethyl oxid or ethyl ether (C2H5)2O, also called, but improperly, sulphuric ether, because prepared from a mixture of sulphuric acid and alcohol.
- n. See the adjectives.
- An obsolete form of either.
- A dialectal variant of edder.
- n. A dialectal form of adder.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom
- n. a medium that was once supposed to fill all space and to support the propagation of electromagnetic waves
- n. the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies
- n. a colorless volatile highly inflammable liquid formerly used as an inhalation anesthetic
Middle English, upper air, from Latin aethēr, from Greek aithēr.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Latin aether ("the upper pure, bright air"), from Ancient Greek αἰθήρ (aithēr, "upper air"), from αἴθω (aithō, "I burn, shine"). (Wiktionary)