Old Norse "Mjǫllnir" and Russian "Молния" ("Molniya")


German - Germany
Hi there,

I've read that the name of Thor's hammer Mjǫllnir is related to the Russian word "Молния" for lightning, which makes sense because Thor is the Norse god of lightning and thunder. For example, both the Wikipedia article Mjölnir - Wikipedia on Mjǫllnir and Daniel McCoy (in Thor's Hammer - Norse Mythology for Smart People) at least tentatively link "Mjǫllnir" to "Молния". This link seems to be strengthened by the fact that according to Dr. Jackson Crawford in his video "Norse Myth and Indo-European Myth (Patreon questions)", the Slavic thunder-god Perun (who is quite similar to Thor) has a hammer called "Молния".

There are some additional pieces of information that have to do with this matter:

1. Wiktionary (Mjölnir - Wiktionary) derives "Mjǫllnir" from Proto-Germanic "*meldunjaz" and this in turn from PIE "*meldʰ-n-" (“lightning”).

2. Wikipedia also derives "Mjǫllnir" from Proto-Germanic "*meldunjaz", but derives this from Proto-Germanic "*malaną" ("to grind"), which according to Wiktionary is derived from PIE "*melh₂-" (“to beat, crush, grind”).

3. Wiktionary (молния - Wiktionary)
a) derives "Молния" from PIE "*ml̥dʰ-n-" (“lightning”) and
b) says that "Молния" is probably cognate to "Mjǫllnir".

These pieces of information are a bit confusing. They seem to strengthen the connection between "Mjǫllnir" and "Молния" ((1), (3.b)) and imply that
- "*melh₂-" and "*ml̥dʰ-n-" are cognates ((2) together with (3.a))
- "*meldʰ-n-" and "*melh₂-" are cognates ((1) together with (2)) and
- "*meldʰ-n-" and "*ml̥dʰ-n-" are cognates ((1) together with (3.a)).

Now, what is the correct etymology of "Mjǫllnir" and of "Молния", and how are they related?

Thanks in advance,
  • ahvalj

    Senior Member
    The Russian word (found also in other Slavic languages) is derived (e. g. Derksen R · 2008 · Etymological dictionary of the Slavic inherited lexicon: 333) from the earlier Common Slavic *mildnī~*muldnī "lightning" with close Baltic cognates mentioned in your Wiktionary link. Karulis K · 1992 · Latviešu etimoloģijas vārdnīca. I. A–O: 596 in contrast etymologizes the Latvian word directly from the root Reconstruction:Proto-Indo-European/melh₂- - Wiktionary with the original meaning "to crush" and the secondary metaphoric development towards "hammer" and "lightning". -D- is indeed not necessary (while not excluded) for Latvian, but it is present in Prussian and found dialectally in Slavic (Этимологический словарь славянских языков. Праславянский лексический фонд. Выпуск 20 (morzatъjь–mъrsknǫti) · 1994: 220–222).

    In Germanic, we seem to have only two words, both limited to Norse: Mjǫllnir and myln "fire" (e. g. Germanic etymology : Query result; Orel VE · 2003 · A handbook of Germanic etymology: 266). Orel derives them from, respectively, *melđunjaz and *mulđnjan, i. e. from the same root in two ablaut grades, though, strictly speaking, the latter word can be etymologized in several ways. -Đ- seems to be necessary to explain -ll-.

    Welsh has a similar word Mellt in English - Welsh-English Dictionary - Glosbe, though it is not mentioned in Matasović R · 2009 · Etymological dictionary of Proto-Celtic and I hesitate to guess its original shape.

    To conclude, it seems that a lexeme *meldʰ- (judging from the Germanic đ; I am not sure about the prosodic properties of the Balto-Slavic words) with the meaning "lightning" is attested in Balto-Slavic, Germanic and perhaps Celtic, though with the available material it is difficult to etymologize it further.
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    Senior Member
    American English
    Part of the problem is that the words we're dealing with here might not independently, separately trace back to PIE. Another possibility is that the IE languages in that area could have imported from a non-IE language. Another possibility is that, after PIE broke up into groups such as the predecessors of Germanic, Slavic, & Baltic, a word was retained in one group and dropped in another, but transferred from one such group to another centuries later. The regions in which these languages were spoken are likely to have been adjacent.

    And there's specific evidence that one of those is likely to have happened in this particular case. Not only does Perun have a hammer with a similar name to Thor's hammer, but his own name is also similar to an early name for Thor before he was called "Thor" (something like "Fjorgn"), and they and their hammers have similar powers and they both ride a chariot pulled by goats. That's too much obscure specificity for either culture to have retained so intact since PIE times. Ideas about these characters must have transferred from one group of people to another more recently. And when cultures transfer ideas, they also often transfer the words for them. And a recently transferred word doesn't need to have followed the same phonetic laws that it would have followed it if had been retained in the same language since PIE.
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    German - Germany
    Thank you both for your answers!

    So, according to what I understand, "Mjǫllnir" and "Молния" are probably cognates and derived from "*meldʰ-", and "*melh₂-" is also cognate or even identical to "*meldʰ-". Is that probably correct?

    In his video that I mentioned above, Dr. Jackson Crawford also thinks that borrowing (from each other or from a third party) may be more likely than common heritage.


    Senior Member
    The honest answer is that the evidence is too vague for any definite conclusion: the data available neither explicitly supports nor explicitly contradicts this. Since the words mean more or less the same in the same mythological context and are phonetically close, it is tempting to suppose they have come from the same source — inherited from Proto-Indo-European, or, as Delvo has suggested, spread from one of the daughter Indo-European or substrate languages.

    The connection with *melhₐ- is very speculative: there is no clear trace of the laryngeal in the prosody of the Slavic word, and Germanic looses laryngeals in this position, so it is not indicative either. Even the choice between *dʰ and *d is not clear: in Balto-Slavic it will be only visible in the prosody (for the Prussian mealde this data is unavailable; the Old Russian stress behavior in this particular declension type is ambiguous), and in Norse the dental is assimilated anyway, so we don't know whether it was *đ<*dʰ or *t<*d in what became Mjǫllnir.

    Overall, etymologists try to dissect every Proto-Indo-European word ad infinitum, so that the language starts looking very unnatural: I don't believe, for example, that *phₐtēr "father" is indeed "protector" and *su̯esōr "sister" is indeed *su-hₑeshₐ-ōr "of our own blood", that's interesting as algebraic exercises but not convincing semantically (words of this kind don't evolve this way). Likewise, it is absolutely possible that the lexeme "lightning" in Proto-Indo-European was a word of its own, not derived recently from "to crush" or anything like this.
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