Mottainai (もったいない, [mottainai]) is a Japanese term conveying a
sense of regret concerning waste. The expression "Mottainai!"
can be uttered alone as an exclamation when something useful,
such as food or time, is wasted, meaning roughly "what a waste!"
In addition to its primary sense of "wasteful", the word is also
used to mean "impious; irreverent" or "more than one deserves".
Usage in Japanese Mottainai in Japanese refers to more than just
physical waste (resources). It is even used to refer to thought
patterns that give rise to wasteful action. Grammatically, it
can be used in Japanese as an exclamation ("mottainai!") or as
an adjective phrase ("it feels mottainai"). There is no plural
form. The collection of mottainai things could be called
mottainai koto (もったいない事?). In ancient Japanese, mottainai had
various meanings, including a sense of gratitude mixed with
shame for receiving greater favor from a superior than is
properly merited by one's station in life. Mottainai is a
compound word, mottai+nai. Mott