As I was studying vocabulary today, I happened to come across the titular 十干 which are as follows:
甲（こう）• 乙（おつ）• 丙（へい）• 丁（てい） •戊（ぼ）• 己（き）• 庚（こう）• 辛（しん）• 壬（じん）• 癸（き）
There's a somewhat lengthy definition near the middle of this page.
I happened across this while looking up the word へい（塀 - wall), and the first entry in my プログレッシブ dictionary was 丙（へい）- showing the definition as "3rd rank" or a "grade of C (in school)". I proceeded to find that 甲 and 乙 are also used to mean a grade of A and B respectively.
My questions are:
- Are these used in modern Japanese for ranking things??? If so, all of them, or just like the first 3??? And what kinds of things are ranked this way???
- Is this a part of 尺貫法 or is it something completely separate???
[Side note: would anyone be interesting in making/helping to make a community wiki on 尺貫法? I find it strangely fascinating for some reason.]