mantra, in Hinduism and Buddhism, mystic words used in ritual and meditation. A mantra is believed to be the sound form of reality, having the power to bring into being the reality it represents. There are several types of mantras. Sanskrit verses used in the Vedic sacrifice are known as mantras. Bija-mantra or "seed-sounds," used mainly in Tantra, are syllables without semantic value having an occult affinity for particular deities or forces; use of such mantras usually requires initiation by a guru. Extremely common is the repetition (japa) of the name of a deity and the singing of devotional phrases (mahamantra); for those mantras initiation is not required.