Raksha

In Hindi, Raksha means 'protection'. This word is derived from the Sanskrit language.Raksha is the basic spirit with which the festival Rakshabandhan is celebrated in India. In this festival, a sister ties a string, known as Rakhi, around the wrist of her brother, asking him to protect her. The brother reciprocates by gifting his sister a present and renewing his vow to protect her.Rakshabandham is considered to be a festival that ties two people. A girl can tie a rakhi to a person who is not even her brother but the rule is that she has to continue tieing it all her life. It is so because once a brother, always a brother. You cannot just tie it once and forget about it because when you become brother and sister, the relationship lasts forever.
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[Hindu] In ancient Hindu myth, they are a classification of evil spirits who, on occasion, can sometimes also be friendly. They often battle the gods and are thought to hurt people at night. The Rakshas are led by Ravana, their king, and are the eternal enemies of Vishnu, one of the foremost divinities of the Hindu pantheon. The Rakshas are the descendants of Rishi Kashyapa, a sage and a seer. They usually appear in the shape of a dog or a bird with a fat body, or as a skeleton.

Raksha raksa (Sanskrit) [from the verbal root raksh to protect] A bracelet or amulet; any mysterious token used as a charm or protection.