How would one best combine the Latin “sidereus” and the Greek “σίδηρος” in an otherwise-English-language text to refer to meteoric iron? Ideally in a manner that would be authentic to ancient Roman usage, albeit embedded in a language they obviously never knew.

The best answer here would be a citation of a time a Roman author him-or-her- (optimistic, I know) -self used the words in such a fashion, and then a discussion of how it would be used within English—though of course I doubt such a citation exists. Failing that, knowing how the Romans and/or Greeks referred to meteoric iron would be valuable. This might be combined with information on how the Romans used Greek words within their own text—particularly in a case where the Greek word might be mistaken for a similar-sounding Roman word of a separate meaning—and a synthetic Latin–Greek phrase for meteoric iron using these words could be determined.

My own best guess for this would be just be literally “sideros sidereus,” “stellar iron,” but I don’t know if this is really an authentic way of writing things.

As background, today I learned that the Latin “sidereus,” meaning stellar, of the stars, is strangely similar to the Greek “σίδηρος,” meaning iron. Having studied Latin some in high school, I was aware of sidereus but not of σίδηρος. My understanding is that it is not known whether the two words are etymologically related—and if they are, what the history there is—or if they are just similar by considerable coincidence.

Obviously, one possible connection between the two might be in the notion of “meteoric iron,” as meteorites are occasionally composed substantially of iron, and before the invention of smelting and the Iron Age, would have been one of humanity’s only sources of usable iron. Iron meteorites are even sometimes known as “siderites,” a word that Wikipedia links to σίδηρος rather than sidereus, but seems like it could have gone either way. (“Siderite” is also used for ferrous carbonate, FeCO3, but this compound is not found in meteorites and so clearly must derive from σίδηρος.)

Today, meteoric iron is mostly a curiosity, used primarily just to say you did, for example in jewelry, or in the sword that Sir Terry Pratchett had made for his knighting. It has no practical advantages over the iron we can smelt ourselves. Nonetheless, as Sir Terry noted, meteoric iron, or thunderbolt iron, or star metal, shows up quite a bit in folklore and fantasy, often imbued with potent magics from its travels among the stars. As I am a sometime fantasy writer, specifically in the realm of roleplaying game supplements, where meteoric iron can (and does, say, in Dungeons & Dragons) have special stats and properties, it interests me to think how these interestingly-related words could be combined to refer to this special material.

  • 2
    On the relatedness question: neither word seems to have a secure etymology, but they can't be cognate given known sound laws. Hypothetically one could be a borrowing of the other, but this seems unlikely given the semantic distance; note also that in sīdereus the first vowel is long and the second short, in σίδηρος the other way around. (Also did the ancients know of meteoric iron?)
    – TKR
    Feb 12, 2020 at 1:51
  • @TKR Right, that matches (with greater detail) what I had heard. As for your last question, according to Wikipedia, at least, yes they did—it’s noted as one of the principal sources of iron prior to the invention of smelting, and known to be the material of several ancient items. Whether they knew that the meteorites were from space, rather than just knowing certain rocks had this useful metal, that I don’t know, but it wouldn’t overly surprise me. I have no idea if the Romans knew though—it’s possible that with smelting available, knowledge of meteoric iron waned as it was no longer relevant.
    – KRyan
    Feb 12, 2020 at 2:15

1 Answer 1


You asked about classical usage where a Greek 2nd declension noun is modified by a Latin 2nd declension adjective. I seem to stumble across such examples in ecclesiastical Latin, but I haven't seen examples from Classical myself. So I went looking in Lewis and Short, and examples are hard to come by.

Here's what I've found.

Under arctos I found domitās arctōs. That's because arctos is feminine. Had arctos been masculine, I'm sure it would have been domitōs arctōs

Under ''barbitos'' I found barbitos ulla, since barbitos is feminine too. Had it been masculine, I'm sure it would have been barbitos ullus.

Under melos I found melos longum. Melos is neuter, not masculine.

But although I found no examples of a masculine Greek 2nd declension noun modified by a masculine 2nd declension adjective, I think it is fair to surmise that term you are looking for is sidēros sīdereus, just as you proposed.

Update: Of course, one reason such examples are hard to come by is that the 2nd declension Greek noun was commonly made 2nd declension Latin wholesale. So sidēros sīdereus would be quite apt to become sidērus sīdereus.

  • 1
    Thanks! I’d just about given up on this question, and this is great stuff. So the Romans just used Greek words “as-is” beyond transliteration? Makes sense, considering they (at least the scholars whose works fill most of our available corpus) probably knew Greek well.
    – KRyan
    May 10, 2020 at 21:27
  • 2
    @Kryan Not exactly. Greek and Latin cases don't precisely correspond, so Romans had traditional ways of declining Greek nouns that resembled, but were not identical to, Greek inflections.
    – C Monsour
    May 12, 2020 at 10:15
  • They are often kept, but often not. I looked up sophos, and found some examples, but not modified by adjectives, except for one instance of factus, but then I found it had become factus sophus, rather than factus sophos. The wholesale importation to Latin 2nd declension is quite common.
    – Figulus
    May 12, 2020 at 21:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.