Either vs. Ether — What's the Difference?

Used before the first of two (or occasionally more) given alternatives (the other being introduced by ‘or’)

Ethers are a class of organic compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula R–O–R′, where R and R′ represent the alkyl or aryl groups.

Used to indicate a similarity or link with a statement just made

Any of a class of organic compounds in which two hydrocarbon groups are linked by an oxygen atom.

Used before the first of two (or occasionally more) given alternatives (the other being introduced by ‘or’)

A volatile, highly flammable liquid, C4H10O, derived from distilling ethyl alcohol with sulfuric acid, used as a reagent and solvent, and formerly used as an anesthetic. Also called diethyl ether, ethyl ether.

Used to indicate a similarity or link with a statement just made

The regions of space beyond the earth's atmosphere; the heavens.

One or the other of two people or things

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.

One or the other of two people or things

(Physics) An all-pervading, infinitely elastic, massless medium formerly postulated as the medium of propagation of electromagnetic waves.

Used before the first of two or more coordinates or clauses linked by or

The substance formerly supposed to fill the upper regions of the atmosphere above the clouds, in particular as a medium breathed by deities.

Any one of two; one or the other

(by extension) The medium breathed by human beings; the air.

One and the other; each

(by extension) The sky, the heavens; the void, nothingness.

Likewise; also. Used as an intensive following negative statements

Often as aether and more fully as luminiferous aether: a substance once thought to fill all unoccupied space that allowed electromagnetic waves to pass through it and interact with matter, without exerting any resistance to matter or energy; its existence was disproved by the 1887 Michelson–Morley experiment and the theory of relativity propounded by Albert Einstein (1879–1955).

Any one (of two).

The atmosphere or space as a medium for broadcasting radio and television signals; also, a notional space through which Internet and other digital communications take place; cyberspace.

Each of two; both.

A particular quality created by or surrounding an object, person, or place; an atmosphere, an aura.

Any one (of more than two).

Diethyl ether (C4H10O), an organic compound with a sweet odour used in the past as an anaesthetic.

One or the other of two people or things.

Any of a class of organic compounds containing an oxygen atom bonded to two hydrocarbon groups.

(obsolete) Both, each of two or more.

(uncountable) Starting fluid.

As well.

To viciously humiliate or insult.

Introduces the first of two (or occasionally more) options or possibilities, the second (or last) of which is introduced by “or”.

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.

One of two; the one or the other; - properly used of two things, but sometimes of a larger number, for any one.

Supposed matter above the air; the air itself.

Each of two; the one and the other; both; - formerly, also, each of any number.

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.

Either precedes two, or more, coördinate words or phrases, and is introductory to an alternative. It is correlative to or.

A colorless volatile highly inflammable liquid formerly used as an inhalation anesthetic

After a negative statement used as an intensive meaning something like `likewise' or `also';

The fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies

Any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom

A medium that was once supposed to fill all space and to support the propagation of electromagnetic waves