1. u grčkoj predstavi: plameni vazduh u kome zvezde lebde i bogovi stanuju, dakle nebeski prostor i svetlosna tvar ujedno, nebeski vazduh, nebo;
2. u grčkoj filozofiji najfinija pratvar (Anaksagora, Empedokle, Platon), peti element - kvintesenca - koji ispunjava nebeski prostor iznad Meseca (Aristotel);
3. hem. fina, bistra, bezbojna, lako pokretljiva tečnost karakteristična mirisa, specifično lakša od vode (C4 H10 O);
fiz. tvar koja sem materije u prostoru, po pretpostavci postoji kao sredina u kojoj se zbivaju izvesne pojave u prirodi; npr. energija koju Sunce zrači u prostor prenosi se poprečnim talasima kroz elastičnu sredinu etar, koja je netežljiva, imponderabilna; eter. (grč.)
Alternative form of ether, the hypothetical medium once believed to permeate all of space.
A light volatile flammable liquid C4H10O used chiefly as a solvent and especially formerly as an anesthetic.
ETYM Latin aether, Greek aither, from aithein to light up, kindle, burn, blaze; akin to Skr. idh, indh, and prob. to Eng. idle: cf. French éther.
1. A colorless volatile highly inflammable liquid used as an inhalation anesthetic; SYN. ethoxyethane, divinyl ether, vinyl ether, diethel ether, ethyl ether.
2. A medium that was once supposed to fill all space and to support the propagation of electromagnetic waves; SYN. aether.
(physics) or aether; In the history of science, a hypothetical medium permeating all of space. The concept originated with the Greeks, and has been revived on several occasions to explain the properties and propagation of light. It was supposed that light and other electromagnetic radiation—even in outer space—needed a medium, the ether, in which to travel. The idea was abandoned with the acceptance of relativity.
Its existence was disproved in 1887 by the classic Michelson–Morley experiment, which showed that light travels at the same speed in the direction of the Earth's motion through space as it does at right angles to the motion.
In chemistry, any of a series of organic chemical compounds having an oxygen atom linking the carbon atoms of two hydrocarbon radical groups (general formula R-O-R’); also the common name for ethoxyethane C2H5OC2H5 (also called diethyl ether).
This is used as an anesthetic and as an external cleansing agent before surgical operations. It is also used as a solvent, and in the extraction of oils, fats, waxes, resins, and alkaloids.
Ethoxyethane is a colorless, volatile, inflammable liquid, slightly soluble in water, and miscible with ethanol. It is prepared by treatment of ethanol with excess concentrated sulfuric acid at 140şC/284şF.