Maithuna, the Sanskrit word मिथुन is used in Hindu Tantras (esoteric scriptures) to refer to the sacrament (sacred ritual) of sexual union between husband and wife. Maithuna or Mithuna has various appearances in scripture:
Mithuna: paired, forming a pair; copulation; the zodiacal sign of Gemini in Vedic Astrology, which is depicted as a man and woman in a sexual embrace
Mithunaya: to unite sexually
Mithuni: to become paired, couple or united sexually
By means of the original Tantric Maithuna, after being prepared psychologically and spiritually and initiated by a genuine teacher (guru), the couple learns how to utilize their love and spiritual aspiration in order to transform their natural sexual forces to purify the mind, eliminate psychological defects, and awaken the latent powers of the consciousness. The man represents Shiva, the masculine aspect of the creative divine, and the woman represents Shakti, the feminine aspect and the source of the power of creation.