yakṣa (English spelling) yaksa

Japanese: yakṣa（英語表記）yaksa

…This goddess later becomes the protector of children, but her terrifying appearance before her repentance is linked to the word demon. In the 12th chapter of the Long Agama Sutra, the Yaksha (medicinal spirit, demon) is considered to be the same as a demon. Yakshas live in forests and do good deeds, but also evil deeds. …

From the Eight Guardians

...In Indian art, it is depicted as a cobra or as a human with a cobra on its head. (3) Yaksha, Medicine God (yakṣa): As a forest god, it has both the aspects of a god of good fortune and a demon. Yaksha women (yakṣī, yakṣiṇī) are often depicted as voluptuous nude women, and are considered to be subordinates of Bishamonten.

*Some of the terminology explanations that mention "yakṣa" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…この女神はのちに幼児の保護者となるが，改悛前の恐ろしい姿が鬼という言葉と結びつけられている。《長阿含経》第12〈大会経〉ではヤクシャYakṣa(薬叉，夜叉)が鬼と同類視されている。ヤクシャは森などにいて，善事もなすが，悪事もなす。…