もったいない

1235 is the date attached by Kotobank's Nihon Kokugo Daijiten to an early もたいなし example in 却癈忘記. The later form もったいない is written 勿体無い, and dictionaries connect 勿体 with a thing's proper form, dignity, or value. The kanji are partly interpretive: 勿 means not, and 体 means body or substance, but the spoken Japanese form developed inside Japanese usage. From medieval religious and courtly contexts, the word moved through senses such as improper, irreverent, too good for oneself, and regrettable to waste. Kotobank lists examples from Noh 正尊 around 1541 and the joruri 薩摩歌 around 1711 for exclamatory もったいなや. In daily Edo and modern usage, it also joins related words such as 惜しい, 無駄, ありがたい, and 恐れ多い. Modern もったいない covers more than English wasteful. It can mean that throwing something away wastes its value, that praise is more than one deserves, or that unused ability is regrettable. English usually needs different phrases for those contexts: wasteful, too good to waste, undeserved, or a shame. Example: まだ使えるのに捨てるのはもったいない means it is wasteful to throw it away while it can still be used.