one's inherent nature

original text of a book etc., source / base text (text against which other texts are revised, translated, published, etc.)

head temple / this temple

(music) those pieces of traditional Japanese music composed primarily for the 尺八 (shakuhachi) flute, but also including the 胡弓(こきゅう) (kokyū, “Japanese bowed lute with three or four strings”), and the 琴(こと) (koto)

translator

one's real character

carrying out the real thing without practising; launching into something without practice

本格的: genuine

日本標準時: Japan Standard Time

明細書: a detailed document