Silent and Semi-Silent Vowels in Japanese (Devoicing)

Now we get to an interesting part of the Sounds of Japanese.

Well actually, it’s all been interesting, but this part is something unique.

The official name for the phenomenon that we are going to discuss is called “Devoicing” but since that is a rather weird word, calling this section “silent and semi-silent vowel” is better for comprehension.

We all know what a “silent vowel” is in English, right? It’s when a word contains a vowel, but that vowel is not spoken.

There is a similar, although not exactly the same thing that happens in Japanese. Let’s get into it now.

The [i] and [u] Vowels are Sometimes Silent

Alright, so there are five vowels in Japanese, remember? And of those five, two of them are sometimes silent. They are the [i] ad [u] vowels.

Now the big question is this: “When are they silient?”

The answer goes back to the discussion on “voiced” consonants and “un-voiced” consonants. You remember that part? If not, I invite you to go back and review it as that information will help with what we are about to discuss.

Anyway, the simple rule is this: When the [i] or [u] vowel occurs between two unvoiced consonants, it is silent.

This is something that you might have picked up on already if you’ve listened to a lot of the Japanese language already, but if not then don’t worry as I will continue to explain it all.

Basically, there are a few consonants that are considered “un-voiced” and they are:

  • [k]
  • [s]
  • [t]
  • [h]

So anytime you have a word that has one of the above consonants, followed immediately by [i] or [u], and then again immediately followed by another of the above four consonants, the [i] or [u] vowel sounds as if it is dropped.

Let me show you a few words that illustrate this concept right now.

  1. I will provide the hiragana first since this is how you will see it written in Japanese.
  2. Then I will show the spelling of it in English since that will help you to visualize it.
  3. And finally I will provide a phonetic spelling of it, which is how we would spell the sound if we were writing dictation.

This third section will be of particular importance to you since it will probably be the closes English transcription of what you are hearing.

As a side note, of course I will also be providing you with some audio so that you can hear it. Let’s begin:





Something else that should be noted at this time is that when an unvoiced consonant and either the [i] or [u] vowels occur as the final mora in a word, the vowel is usually silent. Here are a few common examples:


Also, the example from before somtimes has this silent final vowel:


Again, the important this to note is that these “silent vowels” won’t always be silent. That’s why I also called them “semi-silent” in the title of this post.

Sometimes the speaker will simply whisper these vowels in these situations and it will sound as if the vowel is 90% silent and about 10% audible.

I’ll get into why this happens next.

Why Does This Occur in Natural Speach?

After learning how to make the complete sounds in the last section of this course, you may be wondering why it is that Japanese people omit these [i] and [u] sounds when they appear between two unvoiced consonants.

You might ask yourself, “are Japanese people just being lazy?”

Actually, yes. They are.

Because they have to!

If you’ve ever tried speaking Japanese at a normal conversational pace, you will notice that it is actually kind of hard to fully enunciate these vowel sounds in these particular situations.

In fact, it is much eaiser and feels more natural to silence them in order to speak the whole word in one fluid motion.

Go ahead and try saying the word あした [a-shi-ta] several times over, while fully pronouncing all of the vowels, and at a normal to fast rate.

Then try saying this same word again, but this time go ahead and devoice that [i] vowel [ash-ta].

You should notice quite a different in the effort needed between the two.

Now here’s the kicker: I read that the average person speaks anywhere from 7,000 – 20,000 words per day!

Do you see why it’s actually necessary to silence these two vowels in natural speech?

I hope so, becuase weither you like it or not, you are going to have to learn to recognize it and produce it yourself.

The good news is that, like I mentioned before, it’s actually much more natural to speak this way, so you will become accostumed to is rather quickly with practice.

Anyway, I think I’ve explaned it enough for this lesson. Let’s get into the example words now!

Do You hear it? Do You Not Hear it?

I’m going to go ahead and use the same words that I used above to illistrate the concept. I’ll also throw in a couple of new ones as well.

Listen to how the words actually sound, and don’t allow the way it is written to trick you into thinking it should be pronounced a different way.

Remember: Follow your ears!

あした = Tomorrow

たくさん = A lot

すこし = A little

すき = Like

です = Is

がくせい = Student

たすける = Help

あつくない = Not hot

To-Do List:

For this one I want you to listen to and repeat all of the example words a minimum of three times.

Let me say one thing on mouth placement before we leave this section.

When you silence a vowel like this, it is important to keep you mouth in the correct position as if you actually were going to produce the vowel sound.

This is because the “shh” sound that you make when the [i] is silent is actually different from the “shh” sound you make when you silience the [u] sound.

This concept applies to all the consonant sounds that get combined with silenced vowels!

Try making these two sounds with the vowel now, and then try making the two “shh” sounds without the vowel and see if you can notice the difference between the two silenced “shh” sounds.

  • [shi] – [shu] – [shi] – [shu] – [shi] – [shu]

And then with the vowels all silenced (devoiced):

  • [shh(i)] – [shh(u)] – [shh(i)] – [shh(u)] – [shh(i)] – [shh(u)]

Did you hear it? If not, don’t worry as it will come with time.

Just know that even though [shh(i)] and [shh(u)] only have an audible “shh” sound to them, they in fact sound different from each other due to the different shapes each one requires your mouth to be in when they are created.

And of course this concept applies to all the consonants that have a potentially silent vowel!

Alright, moving on!!!

Continue to Lesson 20!

Questions? Comments? Let me know down below!


Go Back to Lesson 18!

2 thoughts on “Silent and Semi-Silent Vowels in Japanese (Devoicing)”

  1. Thank you for the explanations with illustrative examples on silencing i and u sounds in pronunciation. I have been looking for answers to these stuff for a long time. You have helped me solve one of my biggest obstacles in learning Japanese.

    Warren Kwok

    • My pleasure! This particular topic is, oddly enough, one that very few books or courses ever talk about. I think the only one that I can remember covering this phonetic aspect was Pimsleur.


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