Sound Changes - Part 2 (れんだく)
The Kanji 国, used to represent “country” is very helpful in showing examples of sound changes. Notice that the only on’yomi for 国 is こく.
Unfortunately, that doesn’t mean that 国 is always pronounced as こく！In the previous post, we talked about a sound change that results in reading Kanji characters with そくおん, or the small つ. Here is an example with こっき, the word for “a national flag”:
The Kanji 国 is read with a small つ instead of its normal reading. That is one kind of sound change that happens to Kanji sometimes.
In this post, we’re going to talk about a different sound change that will also change the way you pronounce Kanji characters in certain situations.
Now, let’s talk about Rendaku!
Take a look at these 25 characters:
The upper 20 characters all have what looks like single quotation marks next to them. Those marks are called だくてん. The lower 5 characters have what looks like the degree symbol next to them. Those marks are called はんだくてん.
Those Hiragana characters written without any mark are all voiceless. Once you add a だくてん they become their voiced versions. ぱぴぷぺぽ are somewhere between voiced and unvoiced. This is why the symbol is called a はんだくてん (はん meaning “half”).
All together, these 25 characters are called “voiced obstruents”. OK, now you’re on your way to understanding rendaku!
Let’s do a little exercise. I’m going to give you 7 words. If a character has a voiceless counterpart, I want you to swap the characters. For example, the word こみ would change to ごみ. Remember, only certain characters are able to change!
かみ → がみ
かな → がな
そら → ぞら
しま → じま
たま → だま
つくり → づくり
ち → じ
Notice that つくり becomes づくり and not づぐり. Not every character that can change will change; This is because rendaku only changes the first character!
Characters from the H sound group have 2 possible changes. The tendency is for them to change to their B sound group counterparts.
Therefore words like ほね、ひ、and ふね would normally become ぼね、び、and ぶね respectively. I say “normally” because there are many exceptions.
For now, here is a visualization showing which characters can change because of rendaku:
How Exactly Does れんだく Work?
Rendaku only occurs in compound words. It is when the 2nd word’s first consonant sound changes away from being voiced**. Whew, what a mouthful! Here’s an example for you with our helpful Kanji 国:
The word 中国 means “China”. Knowing the pronunciation of the two words, it’s a bit counterintuitive to pronounce it as ちゅうごく. This is why knowing a little bit about rendaku is important.
Now, here are 7 compound words that use the words I gave you earlier. Next to them, I’ll write the actual readings and meanings.
て + かみ → てがみ (a letter or a note)
ひら + かな → ひらがな (one of the 4 ways to write Japanese)
あお + そら → あおぞら (the blue sky)
なか + しま → なかじま (a Japanese last name)
けん + たま → けんだま (a Japanese cup-and-ball game)
さけ + つくり → さけづくり (sake brewing)
はな + ち → はなぢ* (a nosebleed)
Rendaku can only occur if the 2nd compound begins with one of the 20 characters above. When you have both parts of a compound word that originated in Japan, and the 2nd word starts with one of those characters, rendaku tends to occur. The 7 compound words from earlier are examples.
On the other hand, words that originated in China and other countries tend to block rendaku from occurring. I have to say “tend to” because exceptions are aplenty!
しん + そこ → しんそこ (the bottom of one’s heart)
おく + そこ → おくそこ (depths)
There is no rendaku because even though そこ( meaning bottom) is a Japanese word, both しん (心, meaning heart) and おく (奥, meaning interior, or back part) are words that came from China.
Lyman’s Law and Voiced Obstruents
Remember that “voiced obstruent” is the easy way to group the 25 Hiragana characters I mentioned at the beginning of this post.
Rendaku seems to suffer from a bit of jealousy. Remember that the whole point of rendaku is to make voiced obstruent sounds from voiceless sounds. Well if the 1st word in the compound already has a voiced obstruent, rendaku tends not to happen. If it’s the 2nd word in the compound, it almost always does NOT happen (this is a rule called Lyman’s Law).
みず + たま → みずたま
ざ + ふとん → ざぶとん
はる + かぜ → はるかぜ
With みずたま、みず has a voiced obstruent, so たま doesn’t rendaku. However with ざぶとん、even though ざ is a voiced obstruent, ふとん still undergoes rendaku. When the first word of the compound has a voiced obstruent, rendaku is fairly unpredictable.
はるかぜ follows Lyman’s Law, so because of the ぜ in かぜ、it won’t rendaku. Lyman’s Law is much more reliable when it comes to predicting rendaku.
Rendaku and Avoiding Confusion
There are times when it appears that a word should rendaku but it doesn’t. This is because sometimes, rendaku would lead to a confusing homophone. Here are some examples:
にゅうがく + しけん → にゅうがくしけん
ほうそう + さっか → ほうそうさっか
かん + こく → かんこく
If にゅうがくしけん underwent rendaku it would become にゅうがくじけん which means “a starting school incident”! Similarly, ほうそうさっか would become ほうそうざっか, which means “random broadcasts”. Finally, かんこく means Korea. However かんごく means “prison”. These are mistakes that would definitely get you a strange look if you made them in your conversations! 😅
The opposite situation is also true in rare cases.
As mentioned earlier, ちゅうごく means “China”. However, if you say ちゅうこくthe meaning becomes “advice” or “warning”.
Prefixes That Block Rendaku
The last thing we should talk about is how some prefixes affect rendaku. It turns out that some prefixes actually block rendaku from occurring. Let’s take a look:
① 御 (お or み) Honorific / Respectful Prefix
お + はし → おはし (chopsticks)
② 片 (かた) One-Way or Single
かた + かな → かたかな (one of the 4 ways to write Japanese words)
This is the reason that かな changes to がな in ひらがな; ひら is not a rendaku blocker!
しろ + くま → しろくま (polar bears)
しら + こ → しらこ (a winter delicacy made from cod or salmon)
A quick google search will tell you exactly which part of the cod or salmon is used to make Shirako. (Hint: it can only come from males.) Shirako is definitely not my cup of tea, mainly because of its texture.
まい + とし → まいとし (every year)
はん + しん → はんしん (half of the body)
These are just 5 examples. There are many more out in the wild that you will come across as you learn more and more vocabulary. Also, those prefixes tend to block rendaku; it’s definitely not a guaranteed rule!
There you have it! There is a lot more to rendaku, but I think this is enough information for now.
I find it very interesting how sound changes affect the sounds in compound words. そくおんびん (changing a sound to the small つ) and れんだく can be thought of as two sides of the same coin. Both affect the pronunciation near the midpoint of a compound word. Here is a helpful visualization for you:
As for rendaku, because of how many exceptions there are, I would simply advise you to be flexible when you learn new compound words. If one part of the word sounds “off” a bit, it might be rendaku or sokuon-bin at work! Good luck!
*The Kanji for “blood” is 血. It’s on’yomi is ち so the correct form after rendaku is ぢ. However, you might see “nosebleed” written as はなじ sometimes because ぢ is becoming rarer and rarer nowadays.
**Interestingly, both Kanji sound changes (small つ replacements, called そくおんびん, and れんだく) only occur at the midpoint of compound words. There’s something about the end of the first word and the beginning of the second word that causes these sound changes to happen!
