Can someone explain how 'e' and 'wa' are related in some words / 音便? Presumably the 'e' was originally the obsolete since it's in the ワ行.

Some examples:

  • 上(う) ←→ 上着(う・ぎ)
  • 声(こ) ←→ 声色(こ・いろ)
  • る ←→ 終

(Bonus question: How do you type in the IME? I had to copy it from somewhere else.)

  • ゑ=we for me, at least in google and i believe it was the same in microsoft. it would probably come up as an option for e as well..
    – ssb
    Commented Jan 27, 2014 at 15:54
  • @ssb: FYI, in OSX Kotoeri IME, "we" does not give in the conversion list. "e" did not give it either.
    – istrasci
    Commented Jan 27, 2014 at 15:56
  • 4
    You should be able to get it by typing wye.
    – user1478
    Commented Jan 27, 2014 at 16:02
  • 2
    FYI, your first two cases are part of a more general phenomenen, e.g. 目{め} vs 目{ま}の当たり, 木{き} vs 木{こ}漏れ日.
    – dainichi
    Commented Jan 28, 2014 at 3:49
  • In response to the bonus question: ゑ is "wye" and ゐ is "wyi" in OSX's IME.
    – Kaji
    Commented May 22, 2014 at 3:41

3 Answers 3


There is a whole class of such nouns that exhibit vowel fronting when used as standalone nouns, and not all of them end in -e or -wa. Among other examples, with in-compound forms followed by standalone:

  • 神: かむ vs. かみ
  • 天: あま vs. あめ (also for 雨)
  • 口: くつ vs. くち
  • 目: ま vs. め
  • 手: た vs. て
  • 月: つく vs. つき
  • 木: こ vs. き

One of the reasons for the theory that a certain class of nouns was followed by the now-obsolete Old Japanese い, an emphatic nominalizing particle, is that the term カムイ appears in Ainu as a likely borrowing from Old Japanese or slightly earlier, clearly manifesting a distinct む and a distinct い sound. These two over time could conceivably mush together into み, much as similar sound shifts have been observed in even modern Japanese (such as たかい becoming たけえ, すごい becoming すげえ, etc.) and in other languages around the world.

As to why only certain nouns evince this particular phenomenon, it is not unknown in other languages for there to be specific noun classes. It's possible that these nouns in Japanese might be a vestige of an earlier stage of the language that had such a specific noun class. Notably, a lot of these nouns (at least, the ones I'm aware of) seem to describe parts of the body, spirits, and other concepts that would be personally important. Polynesian languages have a roughly analogous noun class covering so-called inseparables, and these nouns take a specific version of the possessive particle, "no", contrasting with the "na" particle used for possessed nouns outside of this class.

Regarding transitivity / intransitivity and verb conjugation patterns, see blutorange's extensive post about this subject. There are several patterns, of which -わる / -える is just one.


At some point far in the past (before Old Japanese, at least) these words probably had a single form with a diphthong:

上: *upai

声: *kəpai

The diphthong turned into a single vowel differently in different contexts: word-finally it became /e/, and word-medially the /i/ was deleted. (The *p subsequently turned to /ɸ/, which then became /w/ between vowels and later /h/ elsewhere except before /u/ - this is why you have 原 /hara/ and 藤原 /ɸuʥiwara/.)

The 終わる・終える question is a bit different, and has to do with some transitivity-flipping morphology that no one really understands well.

  • 3
    This explanation differs slightly from others I've heard before, which say that the -i was some kind of suffix, maybe a nominative one. I'd be interested to know if you know anything about such competing theories, or if they're really the same, and I'm misunderstanding.
    – dainichi
    Commented Jan 28, 2014 at 3:53
  • I think that's the sort of 'standard' story, but it honestly doesn't make too much sense - if it was an affix, what did it mean; why did it appear on -every- non-compound use of a noun, even with following particles; and why in the world is it restricted to such a small set of words? I think just saying that there were different deletion strategies makes more sense, especially considering that both strategies are used elsewhere in the history of Japonic. (though honestly this is original research on my part :P)
    – Sjiveru
    Commented Jan 28, 2014 at 16:18
  • There is an actual visible suffix -i in kanbun and a few other places, but I seriously doubt it's the same as whatever's visible in these alternations. It never coöccurs with any other particle; and ultimately it doesn't make any sense for it to have merged in some places and not others. This theory of differing deletion strategies also nicely accounts for alternations like shiroi/shira-, though it assumes that the adjective morphology was added later (which makes sense for a few other reasons - one, it's a mess; and two, there's some examples from OJ of bare adjective stems modifying nouns).
    – Sjiveru
    Commented Jan 28, 2014 at 16:22
  • 1
    @Sjiveru Why does -us appear on -every- non-compound use of a first-declension Latin noun? The -i could well have been a "null affix".
    – ithisa
    Commented Jan 29, 2014 at 20:00
  • True, and that's another possibility, but this /i/ appears rather more inconsistently than Latin /-us/.
    – Sjiveru
    Commented Jan 29, 2014 at 21:08

If you look at the classical spellings for your examples the answer becomes obvious rather quickly:

  • 上(うへ)
  • 声(こゑ)
  • 終わる(をはる)

Let's take a closer look at them individually. I'll be using romaji in my explanations because it'll make the relationships clearer as we go.

  • uhe -> uha -> uwa
  • kowe -> kowa

In the case of 終わる ←→ 終える, it's the ワ行 equivalent of a rather common transitive/intransitive pair pattern (cf. 上がる・上げる):

  • woharu -> woheru -> oeru (once modernized)
  • For the nouns, from what I've read, the guess is that the /a/ forms here might be the originals, with the /e/ forms possibly arising as a fusion of final /a/ + /i/ as an Old Japanese nominal particle. That would suggest OJ or pre-OJ /upa/ + /i//upe//uhe/ modernizing to /ue/. Commented May 22, 2014 at 5:57
  • Proto-linguistics isn't my specialty, so I can only comment so much on your post, but I know that OJ dictionaries list /uhe/, etc., so my suspicion is that it would have to be the pre-OJ forms.
    – Kaji
    Commented May 22, 2014 at 6:01
  • I could have been clearer. :) Current dictionaries of OJ are based on modern research. While /upe/ clearly existed in old texts, we don't know if it was considered to be a distinct term unto itself, or if it was instead considered to be a contraction of /upa/ + /i/. That said, you're probably right about it being pre-OJ. Commented May 22, 2014 at 6:06

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .