Different usage of 五


As an [answer](https://japanese.stackexchange.com/questions/12493/whats-the-
difference-between-%E6%B2%BB%E3%81%99-and-%E6%B2%BB%E3%82%8B) to a previous
question, a user stated the following:

> In Japanese this distinction is shown by referring to 自動詞 ("self-acting"
> verbs) and 他動詞 ("other-acting" verbs). Many J dictionaries show this after
> the headword: for example, 新明解国語辞典, highly recommended, gives なおる【自五】 and
> なおす【他五】.

I would like to understand:

  1. How should I read 自五 and 他五? 

  2. What is their exact meaning / translation into English? I understand from the context what they express, but I would like an "official translation".

  3. What is the meaning of 五 in this particular context? 




(I don't think the question is phrased well: it's really about dictionary
abbreviations. Perhaps you can edit it after this answer.)

Remember these are abbreviations, so if you want to read them out helpfully
it's:

自五: ji-go, short for jidoushi-godan 他五: ta-go, short for tadoushi-godan

The 五段 means "5-base (verb)", which has all sorts of other names, including
"4-base verb"(!), meaning the base vowel changes.

Unfortunately the Official Translation (complete with ribbons, legal
certification, and other decoration devoid of significance) is probably
"Transitive" and "Intransitive" (although you still have to define in terms of
Japanese grammar exactly what you mean by that).

If you take another pair: 貸す and 借りる, 新明解 says they are both 他(動詞), presumably
because you both lend and borrow a hammer. So sadly the obvious distinction is
missed by the Official terminology.

Incidentally, this distinction really is everywhere: at the moment there's a
question on the right of this screen: "Difference between 向け and 向き". 新明解
again:

むく【自五】 so "self-acting" and the vowel changes, thus the noun form is むき  
むける【他下一】 so "other-acting" and an "-eru" verb, thus the noun form is むけ




(I don't think the question is phrased well: it's really about dictionary
abbreviations. Perhaps you can edit it after this answer.)

Remember these are abbreviations, so if you want to read them out helpfully
it's:

自五: ji-go, short for jidoushi-godan 他五: ta-go, short for tadoushi-godan

The 五段 means "5-base (verb)", which has all sorts of other names, including
"4-base verb"(!), meaning the base vowel changes.

Unfortunately the Official Translation (complete with ribbons, legal
certification, and other decoration devoid of significance) is probably
"Transitive" and "Intransitive" (although you still have to define in terms of
Japanese grammar exactly what you mean by that).

If you take another pair: 貸す and 借りる, 新明解 says they are both 他(動詞), presumably
because you both lend and borrow a hammer. So sadly the obvious distinction is
missed by the Official terminology.

Incidentally, this distinction really is everywhere: at the moment there's a
question on the right of this screen: "Difference between 向け and 向き". 新明解
again:

むく【自五】 so "self-acting" and the vowel changes, thus the noun form is むき  
むける【他下一】 so "other-acting" and an "-eru" verb, thus the noun form is むけ

