ether

1 of 2

noun (1)

ˈē-thər 

1

a

: the rarefied element formerly believed to fill the upper regions of space

b

: the upper regions of space : heavens

2

a

: a light volatile flammable liquid C₄H₁₀O used chiefly as a solvent and especially formerly as an anesthetic

b

: any of a class of organic compounds characterized by an oxygen atom attached to two carbon atoms

3

a

or less commonly aether

ˈē-thər 

: a medium that in the wave theory of light permeates all space and transmits transverse waves

The concept naturally arose of the ether as a frictionless, incompressible, homogeneous, invisible substance that pervaded all space like a transparent jelly.

—Martin Gardner

b

: airwaves

broadcasting radio signals into the ether

etheric

i-ˈther-ik 

-ˈthir-

adjective

the ether

2 of 2

noun (2)

: the sky

The balloon disappeared into the ether.

plucked an answer out of the ether

—used especially when describing electronic signals that travel through the air

broadcasting radio signals into the ether

sent a message over/through the ether

Examples of ether in a Sentence

Noun (1)

The balloon disappeared into the ether.

Recent Examples on the Web

Noun

The debt buyback also pushed up cryptocurrencies, with bitcoin gaining more than 7% while ether rose over 18%. — Lim Hui Jie, CNBC, 20 Aug. 2026

Dimethyl ether, or DME, is a gas that can be compressed into a liquid at room temperature under 75 psi, a relatively low pressure similar to that of a bike tire. — Idaho Statesman, 17 Aug. 2026

Noun

Hosting gigs at red-carpet events and gossip segments on shows like Wendy Williams and Howard Stern kept his name and face out in the ether, as did his annual South by Southwest party, where lines to enter would stretch around the block. — Shirley Halperin, Rolling Stone, 6 Aug. 2026

But somewhere in the show’s creative journey and the blending of British television veterans and scribes from inside Jackson’s Power-verse, a lot of the specificity vanished into the ether. — Daniel Fienberg, HollywoodReporter, 30 July 2026

Word History

Etymology

Noun (1)

Middle English, from Latin aether, from Greek aithēr, from aithein to ignite, blaze; akin to Old English ād pyre — more at edify

First Known Use

Noun (1)

14th century, in the meaning defined at sense 1a

Phrases Containing ether

• diethyl ether
• ether extract
• ethyl ether
• over/through the ether

Kids Definition

ether

noun

ˈē-thər 

1

a

: an invisible substance once believed to fill the upper regions of space

b

: the upper regions of space : heavens

2

: an easily evaporated flammable liquid used chiefly to dissolve other substances and especially formerly as an anesthetic

Medical Definition

ether

noun

ˈē-thər 

1

: a medium that in the wave theory of light permeates all space and transmits transverse waves

2

a

: a light volatile flammable liquid C₄H₁₀O used especially formerly chiefly as an anesthetic

called also diethyl ether, ethyl ether, ethyl oxide

b

: any of various organic compounds characterized by an oxygen atom attached to two carbon atoms