“a hundred days of sermonizing, one fart” → a metaphor for how something that one has put great effort into can come to nothing after even a slight mistake, much as a hundred days of serious spiritual study can be lost to the winds

Kyūjitai form of 上座部仏教: (Buddhism) Theravada Buddhism

tail gunner

Traditional Chinese (Chinese written using traditional characters)

Simplified Chinese (Chinese written using simplified characters)

UNESCO (the United Nations Educational, Scientific and Cultural Organization)

the North American Aerospace Defense Command; NORAD