na-adjective, noun
Describes something that is legally, functionally, or practically valid, effective, or in force. Common in official, technical, and everyday contexts. Antonym: 無効 (invalid).
Antonyms: 無効
この切符は明日まで有効です。
This ticket is valid until tomorrow.
新しい法律は来月から有効になる。
The new law will take effect next month.
noun
yuko (judo)
A scoring term in judo, awarded for a technique that partially meets the criteria for an ippon. Now obsolete in official IJF rules, but still encountered in older contexts or casual reference.
彼は大外刈りで有効を取った。
He scored a yuko with an osoto gari.