New Study Shows “Burn” Is The Most Metal Word and Lyrically Complex Bands Swear More


Earlier this year, data scientist and ex-physicist Iain published a study on his personal blog, Degenerate State, entitled Heavy Metal and Natural language Processing – Part 1. In this study, Iain uses a corpus of lyrics from 222,623 “metal” songs to perform a linguistic analysis. The results are surprising and lead to some interesting questions about genre and cultural influence. Plus, Iain crowns “burn” the most metal word around. Is your curiosity burning (see what I did there)? Then grab your dictionaries and join me on a wild ride as we uncover some of the most fascinating results of Iain’s study.

Note: I definitely recommend that you read Iain’s original article. He’s the one who put in all the hard work, after all. However, things do get a bit heady near the end, and though you don’t need a degree in data science or statistics to get the gist of what he’s saying, having some understanding of mathematical modeling would certainly enhance comprehension.

As mentioned in the introduction, Iain set out with a goal to test natural language processing techniques, and to delve into metal lyrics to determine if an algorithmic approach could be taken to determine both lyrical complexity and lyrical similarity. Like any good scientist, Iain first proceeded by acquiring a large representative data pool. Iain used renowned heavy metal/hard rock lyrics database Dark Lyrics to develop a corpus of 222,623 songs from 7,364 bands and 22,314 albums. Dark Lyrics is an interesting choice because the site A) is updated slowly and B) lacks lyrics for a huge number of bands. For the sake of comparison, Encyclopedia Metallum boasts a database of 110,134 bands, though obviously not all of these (or perhaps even the majority) have lyrics listed on that site. Limits aside, Iain’s dataset is as good as any to perform statistical modeling, and though the results are not all-inclusive, it would be fair to call them representative.

Dataset in hand, Iain then walked through a series of different modeling techniques to explore complexity and interconnections between bands and their lyrics. The first fruit of Iain’s labor was the figure shown below that plots the proportion of swear words among all words against the readability (determined using the SMOG grade which uses a square-root measure of polysyllables to determine the reading level required to comprehend a piece of natural language) for 100 of the most popular bands on Dark Lyrics. The results, as we can see, are predictable in some aspects, but surprising in others.



Some key findings from the figure:

  • Unsurprisingly, Five Finger Death Punch swears more than anyone.
  • Unsurprisingly, Pig Destroyer, of all the bands used in the model, has the most complex lyrics.
  • Napalm Death and Bolt Thrower require a higher reading level than Bruce Dickinson and Morbid Angel.
  • Twisted Sister seems to use both the least number of swear words and the lowest number of polysyllabic words.
  • Bands that swear more also tend to use more polysyllabic words.

That last fact in particular is exceptionally interesting, but there may be a simple explanation. There are quite a few syllables in the word “motherfucker.”

After performing this simple analysis, Iain then moves onto so-called “bag-of-words” models where the linear order of natural language is broken in favor of searching for the relative frequency of certain words in metal lyrics compared to a corpus of non-metal literature developed at Brown University. By correcting the data using a logarithmic parameter, Iain was then able to determine the 20 most metal words. You definitely should check out the full list on the blog, but the top five most metal words in Iain’s corpus are: Burn, cries, veins, eternity, and breathe. By comparison, the least five metal words are: particularly, indicated, secretary, committee, and university.

On casual examination, it appears that the most common metal words skew more toward the traditional styles of metal, namely thrash, power, NWOBHM, and classic doom. This conclusion makes sense when you consider the fact that Iain understandably culled his corpus from a site that caters toward more well-known metal bands. It’s not hard to imagine the lists may look slightly different if more underground bands were included in the corpus.

After determining the most frequent words, Iain ended his analysis by attempting to algorithmically categorize bands by both the log-likelihood associations of certain words appearing together and the distances between these words. These relationships, mathematically derived through a set of probabilistic distributions and some clever computing, were used to search for other similar log-likelihoods across the whole corpus (like a good statistician, Iain trained his model on 90% of his dataset and evaluated it with 10%), thereby enabling bands with similar likelihoods to be grouped. The figure below presents these findings as a tree-graph where similar bands are color-coordinated.


Click to EMBIGGEN.

Similarly to the other figure, some interesting relationships can be seen in the results:

  • Bands within the same genre (e.g. power metal/symphonic metal in green) tend to be lyrically similar.
  • Bands formed in similar time periods (e.g. the yellow group which features a number of Florida death metal bands and other early 90s bands) tend to group together.
  • Bands with more complex lyrics (e.g. Pig Destroyer and Carcass) are harder to classify.

The finding regarding lyrics seemingly showing when bands were formed is quite curious and seems to intimate, as Iain himself alludes to near the end of his article, that the socio-political conditions of certain time periods tend to affect the birth of genres and the lyrical topics of those genres. Perhaps the 90s bands can all be grouped together because their violent, gory lyrics were a statement against the Reagan-era excesses of the previous decade.

More interesting, though, is the fact that this study, performed purely through quantitative modeling, seems to show some basis for the conclusion that specific genres are rooted in specific lyrical topics. This may seem a foregone conclusion, but most of us, when pressed, would conjecture that we don’t pay much attention to lyrics and that musical style is the only determinant for genre. While stylistic differences are surely the key factor, Iain’s brilliant analysis also seems to show that something else is at play; perhaps there is a sort of subconscious zeitgeist that roots itself in certain language eras and that informs the formation of new genres as much as evolutions in musical style. If this conclusion is true, I can’t wait to see what new genres emerge as a result of this election season.

As I said before, you should definitely take the time to read all of Iain’s article. It’s both fascinating and thought-provoking and presents a meta-analysis of the genre we love so often missing from our own discussions. Iain goes into much greater depth than what I’ve covered here, and I look forward to Part 2.

(All Photos VIA)

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  • Lacertilian

    Cool how tightly that dendrogram ended up linking similar bands. I bet that made the researcher quite pleased.
    Though looking through his article I did notice an error in one of his many formulae. I think I corrected it.
    Where M = metal, log is the logarithmic Randy Blythe insta-constant, and finally one must divide the amount of new metal being released by the amount nü-metal coming out.

  • Dagon

    There are quite a few syllables in the word “motherfucker.”


    Only ToH would throw that in the middle of a “serious” article. This was a great read.

    • BobLoblaw

      It tru do.

  • Janitor Jim Duggan

    I’m at a loss for words about this study. I just don’t get it.

    • Dubbbz

      In simple terms, he counted how often certain words appeared in metal lyrics.

      • Janitor Jim Duggan

        Well that makes more sense. I still don’t get how swearing shows lyrical complexity.

        • BobLoblaw

          In his (very limited) data set there was a correlation.

        • Dubbbz

          So, here’s the thing. Words are qualitative data, so it’s hard to determine any sort of objective measure of them. What’s complex to you may be simple to someone else. In this study, he used some formulas, particularly the SMOG scale, which counts how many words with multiple syllables are used in the dataset, to quantitatively measure and analyze the lyrics.

          • Janitor Jim Duggan

            I have no clue what this stuff means. It is an interesting study though.

          • You are not subjected to understand the method and technique. You can read the correlation tips that Dubs pointed and his conclusion. He summarized very well what the study mean without jumping into statistical fancy pants.

  • Interesting, I thought for sure that one of dead, death, kill or die would’ve topped the list.

  • Janitor Jim Duggan

    Also, does this mean Burn by Deep Purple is the most metal song?

    • CyberneticOrganism


      • Janitor Jim Duggan

        I disagree. The study says burn is the most metal word. That should mean Burn by Deep Purple is the most metal song.

          • Janitor Jim Duggan

            I’m saying that Burn is the most metal song because the song title is the word Burn. I don’t think that if the word burn is in a word in the title that the song counts towards that ranking

          • BobLoblaw

            Youre forgetting they arent metal.

          • Damn, you are are taking this super serial.

          • Dagon

            Why so cereals

        • CyberneticOrganism

          Classic rock ≠ metal

          • Janitor Jim Duggan

            You can’t tell me Deep Purple isn’t metal. They are metal.

          • BobLoblaw

            I just did.

          • Janitor Jim Duggan

            They’re metal. There’s no way around it.

          • BobLoblaw

            A precursor.

          • Janitor Jim Duggan

            Technically they are a precursor but In Rock along with Paranoid are two of the first metal albums ever.

          • CyberneticOrganism

            No blastbeats = not metal

          • BobLoblaw


          • CyberneticOrganism

            It’s true! Find me one Black Sabbath song without blastbeats and tell me I’m wrong.

          • “The sole presence of a blast beat in a certain song, is a true indicator of blistering fucking destructive merol” – Charles Darwin (2016).

          • It’s all coming together now, Link.

          • BobLoblaw

            How far down that rabbit hole do you really want to go?

          • Always, with the blastbeats.

          • CyberneticOrganism


          • BobLoblaw

            I wish i could remember what it was called but there was a VERY old clip of a jazz guitarist playing some crazy stuff that bears resemblance to a lot of tech/prog stuff. Then we could hail him as the forefather.

          • Grandpa’s Magic Fleshlight

            Nope. In Rock is definitely not metal in the least. First two metal bands would be Sabbath and Pentagram, which was definitely more metal than anything DP’s ever done. At most, DP is hard rock when it comes to heaviness.

          • Grandpa’s Magic Fleshlight

            Hahahahahahahaha………………. no.


          • Ayreonaut

            I saw deep purple live last summer for 15 dollars!!!!!!! Even though it’s not the original line up obviously, those guys were fuckin awesome. They played loud and tight and they had tons of energy and did all these sweet extended jams. I’ve always considered the purple to be metal.

          • if you’re just looking for somebody to agree that Deep Purple is a good band, i’ll do it:
            Deep Purple >>>>>>>>>
            now let’s get back to the metal m/

          • I’m going to tattoo that on some foreheads real soon.

        • Ayreonaut

          Or blue oyster cults burnin

    • Señor Jefe El Rosa


  • CyberneticOrganism
    • Dubbbz

      Cybro the Burninator.

      • CyberneticOrganism

        Burninating the BDubs

  • This was a very interesting feature, Dubs. I liked that he used descriptive and correlational statistics all the way as a method to jump into conclusions and classify at the same time (This guy is my idol in this moment for this, srs). The SMOG measure is very interesting, didn’t knew of it and I def see myself checking it out for future general culture readings.

    I find very interesting these topics:

    – Carcass: I remember that Dagon told me once that Carcass even made portmanteus with clinical references, so I am not really sure if that would clash the study a little for using only a quantitative approach to the research problem. That is a common issue in linguistic studies that does not use both kind of scientific methods (cualitative vs. quantitative techniques).

    – My favorite band’s lyrical positions: man, Dark Tranquillity is pretty high of all the melodic death metal bands, and I truly enjoy their lyrical approach. That just reinforce me why I dig some metal band’s lyrics. Other examples: Cradle of Filth, Blind Guardian, Therion or Paradise Lost. Most of those bands are grouped in the bottom left of the first graphic (btw, I didn’t knew how to read in a good way this graphic, I see it as a tendency, maybe someone can explain it to me better).

    – Napalm Death: this just reassures to me that Napalm Death is in a whole different level of lyrical crafting and political stance in the extreme music. Great!

    – I support your correlations conclusions, Dubs!

    – I also support that genres, bands, scenes are def influenced by their local ambient: politics, conformation of the scene, history, climate, social structures and way more variables.

    It would be cool to link this research with a more hermeneutic oriented research, so we can have the best of both worlds in one package, eh? 🙂

    Hails Dubs, Hail Iain, Hail Toilet ov Hell!

    • Dubbbz

      One interesting note in his study is that he considered contractions (like ain’t) one word rather than two.

      • Dagon

        It makes sense to me, speaking as someone who speaks languages but has no formal knowledge about linguistics.

    • Dagon

      Carcass lyrics are interesting. They created some neologisms using suffixes common in medical language.

  • CyberneticOrganism

    Great article btw Dubs, I’m always curious why someone would want to undertake a study like this since it seems A) most metal bands don’t foresee anyone putting this much analysis into how their lyrics stack up to other bands, and B) it seems like a colossal amount of work only to have people like us debate or complain about the results.

    • Dubbbz

      Eh, I think stats can be fun if you’re interested in the topic. For example, I’ve been planning a statistical study related to metal for a while now that will require me to write some programs, but I wouldn’t consider it work because I think the topic is interesting.

      • CyberneticOrganism

        Likelihood of F-150 Ownership and Weekly BDubs Patronage Determined by Musical Preferences: A Statistical Analysis

        – Dubbbz

        • Dubbbz

          Causation does not equal correlation, Cybro. 😉

      • Dagon

        It’s just good natured nerdy fun

      • Statistical analysis makes my underbits soft.

        • Dubbbz

          Would it make your underbits hard again to consider it sorcery, because a lot of it more or less is sorcery.

  • Abradolf Lincler

    its nice that at least some portion of these bands are actually metal. i have seen similar studies claiming to show literacy levels based on different genres lyrics, metal was never metal. hip-hop was always like a 2nd grade reading level lol.

  • Elegant Gazing Globe

    you have way too much spare time on your hands

  • tigeraid

    My guess was “poser” and “slay.”

    • Dubbbz

      That’s a wager you would lose.

    • Grandpa’s Magic Fleshlight

      Or “steel”.

  • frozengoatsheadupanunsarse

    Right-o, who wants to collaborate on a spoken word librarian grind project?

    • Dubbbz

      Some dude on facebook promised us a spoken word rendition of St. Anger

      • frozengoatsheadupanunsarse

        Me wantee!

  • Hans Müller

    So if your genre isn’t niche enough, you can compensate by singing about secretaries at university and the committees they form there. Cool!

    Also, this song just became even more metal:

  • EsusMoose

    Awesome article, will have to look into the og study later

  • Ayreonaut

    Hearts on fire hearts on fire burnin burnin with desire

    • Grandpa’s Magic Fleshlight

      Good song, hilariously lolbuttz video.

      • Ayreonaut

        Unfortunately I saw the video first so the song is quite possibly ruined for me as that is all I ever think of when I hear it. The same damn thing happened to me with bewitched by candlemass

  • Dave Vincent’s Perm
  • Waynecro

    Awesome work, Dubs! Thanks for breaking down all the mathy bits for us.

  • TOILET OV SMARTYPANTSES! ( Top Shelf stuff here Dubz.)

  • Kyle Reese

    Particularly Pretty Secretary – Lost Twisted Sister B Side