What do double letters actually do?

Have you ever wondered why some words have double letters (ya know, like the word "letter")? Well, English isn't the only language to do so and, in fact, double letters actually have a useful role in other languages.

We can break the idea of double letters down into two categories: double vowels and double consonants, the latter of which is called gemination from the Latin word gemini, or "twins."

Let's take a look at double vowels first since it's a little easier to understand than gemination. For this, we'll focus on Dutch.

Double Vowels

If you've ever seen written Dutch or have a friend with a Dutch last name, you've probably noticed that there's a lot of double vowels. In Dutch, the vowels are "a," "e," "i," "o," and "u," just like in English. However, you'll also see "aa," "ee," "oo," and "uu," like in the name Johannes Vermeer or Afrikaans, the Dutch spoken in South Africa.

So what's the point of these double vowels? Did someone just lean on their typewriter too hard one day in Amsterdam and start a frenzy of double letters?

Well, not exactly. In the case of Dutch, the double vowels exist to denote long vowels, while a single vowel represents a short vowel. Some languages do this using diacritics (accent marks, like the macron in Latin), but Dutch decided to do this using two vowels.

By long vowel, I don't necessarily mean that you make the same sound as the short vowel but hold it for longer (although the long vowels do end up lasting for a bit more time). Rather, the vowel sound actually changes. One example is "ee," which has a sound similar to the "ai" in "main," or "ea" in "tear" if it comes before an "r." A single "e" has a short sound like the "e" in "get," but adding one more "e" changes the sound. This website has a couple of examples that you can hear.

And, well, that's basically all there is to it. It's a lot more consistent and logical than English, where something like "oo" can have one sound in "door" and another in "shoot." But, of course, English is known for its messy grammar with loads of exceptions.

Other notable usages of double vowels occur in Finnish, Estonian, Lombard (an Italian dialect), Afrikaans, and West Frisian (a language of the northern part of the Netherlands that is considered the closest relative to English). As a fun aside, Estonian actually sometimes takes the idea of a double vowel a bit too far and you can get words like kuuuurija, which means "moon researcher." And no, that isn't a typo; it is in fact four u's in a row!

Now that we've covered some double vowels, let's look at some double consonants. For this, we'll mainly examine Italian.

Double Consonants

Gemination (the technical term for double consonants) is a very common feature of Italian and is part of what gives it that musical, bouncy sound.

Basically, gemination is the lengthening of a consonant sound due to the presence of two consonants. Gemination can occur with numerous consonants, such as "c," "f," "g," "l," "p," and "t," to name a few. Instead of the quick sound that we would expect from each of these consonants as we are used to in English, if these consonants were geminated in Italian, their sound would last longer, change the stress in the word, and alter the surrounding vowel sounds.

This isn't just a purely aesthetic or phonetic occurrence, though. Gemination actually serves a function, namely to distinguish between words. For example, the words fato and fatto look different, but in English we'd probably pronounce them in the same way. However, in Italian, these are two completely different words and are pronounced differently to reflect that. Fato is pronounced with a fast, short [t] sound and means "fate" while fatto is pronounced with a long [t:] sound and means "fact."

If you say both of these words out loud, you'll notice that in order to say fatto, you need to extend the length of the "t" and it sort of has that bouncy feeling that makes Italian so musical. Since many words in Italian feature gemination, in rapidly spoken Italian, the stress and tone go up and down in a sing-song way that makes the language so beautiful.

Of course, Italian isn't the only language to feature gemination, just as Dutch isn't the only language to have double vowels. Other languages such as Arabic, Danish, Latin, Hindi, Polish, Russian, Punjabi, and Norwegian also feature double consonants that change the meaning of a word.

Languages like English and French have double letters (again, look at the word "letter") but the distinction usually doesn't mean anything. "Letter" could just as easily be spelled "leter*" or "letr*" and the pronunciation would be the same. The fact that English and some other languages have double letters is just a vestige of an older form of the language.

The concept of double letters, whether it is vowels or consonants, is actually grounded in various different linguistic ideas that would be far too much for this simple introduction. In future posts, I will discuss some of these ideas (phonetics, phonemics, morphology, and IPA transcription, which I kind of hinted at above), but for this post I just wanted to address something that I had always wondered about spelling.

If you've never come across the idea of double letters before, or have wondered why they're a thing, I hope this introduction helped. If you're learning a language that has a functional use for double letters and were confused about what exactly the meaning was, hopefully this clarified some things.

Check out the sources below in case you're curious to learn more about this cool linguistic idea!

References

1. http://www.dutchgrammar.com/en/?n=SpellingAndPronunciation.10

2. https://en.wikipedia.org/wiki/Dutch_orthography

3. https://en.wikipedia.org/wiki/Gemination

4. https://repository.upenn.edu/cgi/viewcontent.cgi?article=1665&context=pwpl