About 4500 years ago, people in what is now Ukraine spoke a language which linguists have reconstructed and call Proto-Indo-European (PIE).

As these people fanned out east and west, PIE split up into dialects which evolved into hundreds of languages that we know today, including English, Spanish, German, Russian, Persian, and Hindi.

The Dawn of Aurora

The PIE root *h₂ews- (the asterisk indicates a reconstructed form — no written records of PIE exist) meant "to dawn, to become light, to glow". The h₂ consonant "colored" the following vowel into an "a" sound, so we can think of this root as becoming pronounced more like "aus" (rhyming with English "mouse", for example).

The noun formed from this root, meaning "the dawn", was *h₂éwsōs.

One of the branches that PIE sprouted was Proto-Hellenic, the ancestor of Greek, and here *h₂éwsōs became *auhṓs, with first s becoming an h between vowels.

In the Attic (that is, Athenian) dialect of Greek this became ἠώς (ēṓs), "dawn". We use this in words like the Eocene ("dawn-new") Epoch, the period when many modern mammal orders appeared, including primates (yay, humans!), elephants, and horses, such as the Eohippus ("dawn-horse)".

The Greeks used this as a proper noun, because they worshiped Ἠώς (Ēṓs), the goddess of the dawn.

Folklorists see a deep Indo-European origin for this dawn goddess, because she is also found in the Sanskrit form उषस् (Uṣás), while the Proto-Italic *auzōs became the Latin Aurōra.

This, of course, gave us the names for the Aurora Borealis and the Aurora Australis ("northern dawn" and "southern dawn").

Not to mention Wayne and Garth's hometown.

Eldorado

Another Proto-Italic root from *h₂ews- is *auzom, meaning "gold", that is, that stuff that glows like the dawn.

This became Latin aurum and eventually Spanish oro. If something is gilded in Spanish, it is d-or-ado. The 16th-century Spanish conquistadors scoured Colombia, looking for "the gilded man": El Dorado, and the legendary city of gold named for him.

This rumor arose from the very real custom of the king of the Muisca people to be coated in gold dust and then leap into Lake Guatavita.

They never found their city of gold, but a ྲྀ Cadillac Eldorado is now about worth its weight in gold.

Austria (and Australia), air, and malaria

The PIE suffix *-teros formed adjectives, so *h₂éws-teros meant having to do with the dawn or, more specifically, in the direction of the dawn.

In the German branch, this word became *austraz, which evolved into the English "east".

The Old High German name for the "eastern realm" was Ostarrîchi, which became modern-day Österreich. In the 12th century, this was Latinized to Austria.

This is odd, because the Latin auster doesn't mean "east", but rather "south" for some reason. Even though auster also comes from *h₂éws-teros! But this meaning of "south" is why we call that southern hemisphere continent "Australia".

It's also why the Southern Lights are called the Aurora Australis. So the two parts of this name together mean "the dawn-directioned dawny-thing".

Another PIE form derived from the root is *h₂éws-r̥h₂ (pronounced "awsra", pretty much). This entered Proto-Hellenic as *auhrā, which became the Greek αὔρᾱ (aúrā) with the meaning "cool breeze" or "steam". In English, "aura" now has the sense of an atmosphere.

And the form *h₂ews-ḗr "morning mist" lost the s going into Proto-Hellenic as *āwḗr and ending up as the Greek ᾱ̓ήρ (āḗr), whence our English "air".

This was borrowed into Latin as āēr, which ended up in Italian as aria.

"Aria" came to mean a kind of song ("air") sung during an opera.

Before it was understood to be a mosquito-borne disease, the ancient Romans thought it came from "bad air", so they called it mal-aria.

Earendil and Vandals

But what about the Germanic branch? Didn't any other word filter down to English besides "east"?

Glad you asked!

If your a Tolkien fan, you'll be interested in learning that the Proto-Germanic word for the Morning Star (that is, the planet Venus as it appears in the morning) was *Auzi-wandilaz, literally "Dawn-wanderer". (The *wandilaz part was the source of the name of the Germanic Vandal tribe — the ones who sacked Rome in 455.)

In Old Norse this name is found as Aurvandill.

In Norse mythology, Aurvandill's toe froze when Thor was carrying him in a basket across the Élivágar rivers. Thor tossed Aurvandill's toe into the sky, where it turned into a star.

In Anglo-Saxon (Old English) this name appeared as Ēarendel.

In 2022, the Hubble Space Telescope discovered the (to date) most distant known star — 28 billion light years away! — and named it "Earendel".

J.R.R. Tolkien modified the spelling to Earendil and used it for the name of his half-elven hero of the Silmarillion.

Please see my other "Where Words Came From" stories!