What are the origins of ド when used as emphasis, and is it always negative?


Sometimes I've seen ド as a prefix that adds emphasis to words. So saying
someone is ドバカ is saying that they are much more stupid than just バカ.

I'm wondering what the origin of ド in this context is. Does it come from 度
【ど】("degree"), as in, "the degree of X is higher"?

Also, is it always negative? I usually see it attached to negative terms, but
I don't know if it's exclusively negative.

Lastly, is it impolite?




In present Japanese, the usage is not limited to negative terms

> ど真ん中 'right in the middle', 'bingo!'  
>  ど根性 'strong guts'

but does not seem to be productive either (i.e., usage is limited). When it is
used with a negative term, that is surely impolite, but the words listed above
are not particularly impolite.

`ど` seems to have derived from the 18th century form `どう`, whose meaning is
not clear. There is another descendant form `どん`, which developed mainly in
the context of kabuki (歌舞伎), and seems to be used only for negative terms.

> どん尻  
>  どんケツ  
>  どん引き [Recent slang]

Here are some discussions on other sites:

  * <http://kotobakai.seesaa.net/article/8237957.html>
  * <http://d.hatena.ne.jp/nobita720/20110702>




In present Japanese, the usage is not limited to negative terms

> ど真ん中 'right in the middle', 'bingo!'  
>  ど根性 'strong guts'

but does not seem to be productive either (i.e., usage is limited). When it is
used with a negative term, that is surely impolite, but the words listed above
are not particularly impolite.

`ど` seems to have derived from the 18th century form `どう`, whose meaning is
not clear. There is another descendant form `どん`, which developed mainly in
the context of kabuki (歌舞伎), and seems to be used only for negative terms.

> どん尻  
>  どんケツ  
>  どん引き [Recent slang]

Here are some discussions on other sites:

  * <http://kotobakai.seesaa.net/article/8237957.html>
  * <http://d.hatena.ne.jp/nobita720/20110702>

