ether

American  

[ee-ther] / ˈi θər /

Also aether

noun

1. Also called sulfuric ether.  Also called diethyl ether.  Also called ethyl ether,.  Also called diethyl oxide,.  Also called ethyl oxide,.  Chemistry, Pharmacology. a colorless, highly volatile, flammable liquid, C 4 H 10 O, having an aromatic odor and sweet, burning taste, derived from ethyl alcohol by the action of sulfuric acid: used as a solvent and, formerly, as an inhalant anesthetic.

2. Chemistry. (formerly) one of a class of compounds in which two organic groups are attached directly to an oxygen atom, having the general formula ROR.

3. the upper regions of space; the clear sky; the heavens.

4. the medium supposed by the ancients to fill the upper regions of space.

5. Physics. a hypothetical substance supposed to occupy all space, postulated to account for the propagation of electromagnetic radiation through space.

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ether British  

/ ˈiːθə, iːˈθɛrɪk /

noun

1. Also called: diethyl ether.   ethyl ether.   ethoxyethane.  a colourless volatile highly flammable liquid with a characteristic sweetish odour, made by the reaction of sulphuric acid with ethanol: used as a solvent and anaesthetic. Formula: C 2 H 5 OC 2 H 5

2. any of a class of organic compounds with the general formula ROR′ where R and R′ are alkyl groups, as in diethyl ether C 2 H 5 OC 2 H 5

3. the hypothetical medium formerly believed to fill all space and to support the propagation of electromagnetic waves

4. Greek myth the upper regions of the atmosphere; clear sky or heaven

5. a rare word for air

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ether Scientific  

/ ē′thər /

1. An organic compound in which two hydrocarbon groups are linked by an oxygen atom, having the general structure ROR|||PRIMARY_STRESS|||, where R and R|||PRIMARY_STRESS||| are the two hydrocarbon groups. At room temperature, ethers are pleasant-smelling liquids resembling alcohols but less dense and less soluble in water. Ethers are part of many naturally occurring organic compounds, such as starches and sugars, and are widely used in industry and in making pharmaceuticals.

2. A colorless, flammable liquid used as a solvent and formerly used as an anesthetic. Ether consists of two ethyl groups joined by an oxygen atom. Also called diethyl ether, ethyl ether. Chemical formula: C ₄ H ₁₀ O.

3. A hypothetical medium formerly believed to permeate all space, and through which light and other electromagnetic radiation were thought to move. The existence of ether was disproved by the American physicists Albert Michelson and Edward Morley in 1887.

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Other Word Forms

• etheric adjective
• superether noun

Etymology

Origin of ether

First recorded in 1350–1400; Middle English, from Latin aethēr “the upper air, pure air, ether,” from Greek aithḗr, akin to aíthein “to glow, burn,” Old English ād “funeral pyre,” Latin aestus “heat”

Example Sentences

But in the making of her 2025 album “Sincerely,” she explored the profound vulnerability of becoming a mother — and her sighing revelations in “Sugar! Honey! Love!” melt most beautifully into the hazy pop ether.

From Los Angeles Times

The band moves in the fertile periphery where sunshine pop meets dream rock, channeling the Police on the reggae vibe of “Universal Hit” and diving into Cocteau Twins ether on “La Vuelta.”

From Los Angeles Times

“I wanted to step back from any type of risk,” said Cancel, who still holds some ether.

From The Wall Street Journal

In 1867, Lord Kelvin pictured atoms as tiny knots in an invisible medium called the ether.

From Science Daily

The music was in my head or, if you are willing to get spiritual about it, in an unidentifiable ether.

From Los Angeles Times