Mottainai

 is a term of Japanese origin that has been used by environmentalists. The term in Japanese conveys a sense of regret over waste; the exclamation "" can translate as "What a waste!" Japanese environmentalists have used the term to encourage people to "reduce, reuse and recycle", and Kenyan environmentalist Wangari Maathai used the term at the United Nations as a slogan to promote environmental protection.
Etymology, usage, and translation.
"Kōjien", widely considered the most authoritative Japanese dictionary, lists three definitions for the word (classical Japanese terminal form ): (1) inexpedient or reprehensible towards a god, buddha, noble or the like; (2) awe-inspiring and unmerited/undeserved, used to express thanks; (3) an expression of regret at the full value of something not being put to good use. In contemporary Japanese, is most commonly used to indicate that something is being discarded needlessly, or to express regret at such a fact. , then a professor at Nagano University, noted that the definition (3) in "Kōjien" was the one used most frequently by modern Japanese. The second sense is seen in Japanese newspapers when they refer to members of the imperial family as having been present at such-and-such an event, not necessarily implying wastefulness but rather gratitude or awe. "", another Japanese dictionary, gives a similar ordering of these definitions. 
Hasegawa traces this increase in the frequency of meaning (3) to a historical semantic shift in which the original meaning, meaning (1), became less prominent. Citing the Kyoto University Japanese literature scholar , Hasegawa states that the word originated as slang in the Kamakura period, and that by the mid 15th century had perhaps already acquired the meanings of (2) and (3). 
Two frequently-cited early examples of usages of , given in both "Kōjien" and "Daigenkai", are the "Genpei Jōsuiki" and the "Taiheiki". A form of the word, (モタイナ) appears in the late-14th or early-15th century Noh play "", apparently in a sense close to (1).
The word in resembles a Japanese negative ("there is no "), but may have originally been used as an emphatic ("tremendous "). itself is a noun appearing as such in, for example, the dictionary "", which dates to 1444. "Daigenkai" gives as an alternate reading of the word, and it appears written with the kanji , , , , or . It means (i) the shape/form of a thing or (ii) something that is, or the fact of being, impressive or imposing (; ). The compound that is pronounced as in Japanese appears in Sino-Japanese dictionaries as a Chinese word in a sense similar to (ii), but does not, as it is an indigenous Japanese word.
The 18th-century Kokugaku philologist Motoori Norinaga, in the preface to his 1798 treatise "Tamaarare" ('Ice Crystals (like) Jewels'; ) designed to stir people up from their sleepy acquiescence in acquired customs that were not authentically native, and was critical of the use of the word to express gratitude. He felt its use for such a purpose (along with those of and ) was vitiated by its ultimate derivation from imitating forms of Chinese rhetoric and greetings. In his 1934 essay "Nihon-seishin to Bukkyō", the Buddhologist Katō Totsudō (; 1870-1949) included the "aversion to wastefulness" () in a putative series of what he considered to be "core Japanese personality traits".
Modern Japanese environmentalism.
In November 2002, the English-language, Japan-based magazine "Look Japan" ran a cover story entitled "Restyling Japan: Revival of the 'Mottainai' Spirit", documenting the motivation amongst volunteers in a "toy hospital" in Japan to "develop in children the habit of looking after their possessions", the re-emergence of repair shops specializing in repairing household appliances or children's clothes, the recycling of PET bottles and other materials, the collection of waste edible oil, and more generally the efforts to stop the trend of throwing away everything that can no longer be used, i.e. the efforts of reviving "the spirit of ". In that context, Hitoshi Chiba, the author, described as follows:
In a 2014 paper on an apparent increase in interest in the idea of in early 21st-century Japan, historian Eiko Maruko Siniawer summarized the views of several Japanese writers who claimed that was a specifically Buddhist concept. She also cited a number of views of Japanese authors who believed that it was a uniquely Japanese "contribution to the world", whose views she characterized as mostly being "deeply rooted in cultural generalizations, essentialisms, and disdainful comparisons between countries".
Use by Wangari Maathai.
At a session of the United Nations, Kenyan environmentalist Wangari Maathai introduced the word as a slogan for environmental protection. According to Mizue Sasaki,
Maathai worked to popularize the word in places outside Japan. At the 2009 United Nations Summit on Climate Change, she said, "Even at personal level, we can all reduce, re-use and recycle, what is embraced as Mottainai in Japan, a concept that also calls us to express gratitude, to respect and to avoid wastage."