How do you remember redaku'd / っ'd readings?

The mnemonics in WaniKani are definitely working their magic. I’m on level eight right now, so I’ve got a long way to go; but I feel like I have a pretty solid grasp of the kanji and vocab meanings so far, and most of the readings.

The biggest trouble I’m running into is with the vocab words that are made up of two kanji and no hiragana. Remembering which of these get the stupid little adjustments, like dropping the last syllable of the first kanji’s on’yomi reading, or redaku-ing the first syllable of the second one. And WaniKani’s just kind of like, “you just have to remember.” But how tho, WaniKani?! :weary:

I’m starting to be able to remember from the way the readings sound on some of them-- like how the reading for 作家 sounds like soccer, and the reading for 欠点 sounds like kitten. But I don’t know that this approach will be sustainable as I move up past level 10.

How do you guys remember these little alterations in certain vocab readings? Do you have any tricks or mneumonics that you use to help you remember them?


Here’s a guide that gives you some rules of thumb for rendaku that can hopefully help you:

Cliff Notes:

  1. Japanese origin words do rendaku.
  2. Chinese origin word do not rendaku.
  3. Foreign loanwords do not rendaku.
  4. If the second word in the compound has a voiced consonant or handakuon anywhere in it, rendaku does not occur.
  5. If voicing in the first word is too close to the second word, rendaku may not occur.
  6. In words that come together to mean “X and Y,” rendaku does not occur.
  7. Repeating onomatopoeia do not rendaku.
  8. Certain prefixes and suffixes cause rendaku not to occur.

Try saying けってん and けつてん a bunch. Which is easier to say? You’ll get good at “just knowing” eventually based on that kind of thing.


Totally going to spend some time memorizing these rules of thumb! And the article looks really in-depth and exhaustive, so I’m looking forward to diving in to that later.

Gosh I hope so. I guess I need to start incorporating speaking into my review routine instead of just passively listening.

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If the first kanji ends in く, ち or つ and the second kanji begins in an unvoiced kana, it’s a 99.9% chance that a germination will occur. That’s a good rule of thumb.

Another advice I’d give is that you should try your best to memorize the word based on the reading, and not the kanji. What I mean is: learn the word as けってん and burn it into your memory as such, don’t store it in your brain as “fault + point”. Then, in reviews, use the kanji to sound out what the word would sound like and see if it matches anything in your memory. For example, you’d see 欠点 and think “Do I know けつてん? Hmmm, doesn’t ring a bell. What if I try to germinate it? Oh, I know けってん, nice!” or something like that. This is how I focus on learning new words. There’s a lot of words that I know through exposure that I have no idea how to write in kanji, but if I saw the kanji for it somewhere I’d just attach it to what I already know.


Also just to be clear you do know that 欠点 → けってん is not rendaku right? That’s consonant gemination. Just want to ask just to make sure you don’t confuse the two concepts in your head as being the same thing.


Even if you just say out loud what you’re reading, I think it helps.


This seems too simple-- is it really true?? I hope so; going to keep this in mind!

This is basically the exact 対 (just learned that kanji this morning :slightly_smiling_face:) of what I’ve been doing, but I totally see how this could make what I’m learning far more useful practically. Rn, it’s a long way to go from “ok, what does this kanji + this kanji mean?” → “what were the on’yomi readings for each?” → “can I just slap those readings together or do I need to redaku?” → correct pronunciation (or at least my best guess). If I focused more on connecting the sounds to the meanings, I think that really would shrink the processing time considerably.


Yep, in lieu of speaking just shadowing the vocab audio can be helpful.


Yeah, you’re right, it’s not rendaku, it is gemination. :smiley:

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Yeah, it’s pretty common. I don’t think you’ll see the ち case as much (even if it’s still true), but you’ll see words with the く and つ cases literally all the time. Check this out to see how common it is. :slight_smile:


Sometimes they do. But it’s a lot rarer, and I think the rendaku versions are technically considered just another on reading…

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Thanks for pointing this out. Yes, I did know it wasn’t rendaku, but I didn’t know what it was called or why it happens sometimes. Now I know what to look up to try and get a handle on this aspect of compound word pronunciation! :slightly_smiling_face::+1:

Yeah, I def need to do this consistently. I use WaniKani on my phone, and I’m often out in public when I’m doing my lessons-- so I’m not inclined to say words out loud. But even just mouthing or whispering the words to myself will probably make a big difference.


:+1: Like I said, just making sure. Some people do get the two confused with each other.


I have a small vendetta with those who call gemination a glottal stop. IT IS NOT A GLOTTAL STOP!!!


Well, as Kristen wrote, those rules are not 100%.

WARNING: While we are calling these “rules,” they’re more like guidelines. Rendaku can be difficult to understand because it’s riddled with exceptions and can be unpredictable. These “rules” exist to help you get a better idea of how and when to predict rendaku, but they’re in no way absolute or unbreakable. Language is tricky like that.

And why you see this line under the kango word section:

That doesn’t mean all kango compounds don’t rendaku though. Rendaku also occurs in kango sometimes, especially if the second element is vulgarized . Vulgarization, in the linguistic sense, simply means to make a word common. Because it’s part of the general language, it’s treated like it is a wago word.

That’s why the key part of my statement was ‘rules of thumb’. :slight_smile:


Wait, hold on-- did we mean to say that ち, く, and つ cause rendaku 99% of the time, or that they are swapped for the little っ 99%? :thinking:

Thanks for pointing this out. I feel like calling those an “alternate reading” is just a cop-out :roll_eyes:

Yeah, by all means, correct me wherever you can!! I can’t learn if no one tells me I’m doing it wrong. :upside_down_face:

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Wait, there’s a difference?

Also, does “the sokuon” refer only to the actual character 「っ」 and not the sound it makes? Phonetics are confusing :sob:

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Glottal stop, I believe, would be the っ at the end of a word or when it’s an exclamation like ああっ!


I’ll just also say that a lot of this does become intuitive after a while even if you don’t make any efforts to learn it specifically

Also, some words are almost always rendaku’d when they’re preceded by other kanji. Like 人 => びと, 部屋 => べや, 口 => ぐち. To the point that it trips me up when this does not happen…

For example, is the fact that 早口 is はやくち part of any of these rules of thumb? Because this one trips me up a lot :slight_smile: