Somewhat mysterious awareness of
what's happening or will be happening around. It is often confused with unagi, which is likely an English transcription of Japanese word 鱼炙, meaning grilled fish and often referring to a popular Japanese dish of eels. Oonagi, on the other hand, is likely an English transcription of Japanese word 悟机, which means
understanding the signs (of the universe) and is often seen in spiritual and martial arts literature. Such
understanding enables one to sense what might be or will be happening and therefore avoid danger or be prepared for it.
It is said that Master Tashin acquired oonagi after 49 days of
meditation under an old pine tree in Mount Asahi. He was often seen
going back to
the palace (that's usurped by his evil brother) but the guards were never able to seize him.