1.
relative merit, superiority/inferiority, ranking difference
The difference in quality or rank between two things; used to discuss whether one is better than another.
甲乙つけがたい。
Hard to say which is better.
二人の実力には甲乙がない。
There's no difference in ability between the two.
両案は甲乙つけがたい内容だ。
Both proposals are of comparable quality.
2.
Party A and Party B (in contracts)
Designations for the two parties in a contract or agreement.
甲乙 has two distinct uses: comparing merit and contract designations.
ORIGIN:
甲 and 乙 are the first two of the ten Heavenly Stems (十干) from ancient Chinese ordinal systems.
COMMON EXPRESSION:
甲乙つけがたい: hard to rank, equally good/bad
IN CONTRACTS:
- 甲: Party A (often the more powerful party)
- 乙: Party B
- Sometimes extended: 丙 (C), 丁 (D)
RELATED:
- 優劣: superiority and inferiority
- 比較: comparison