Tantra

Tantra (Sanskrit: तन्त्र, "loom, warp"; hence "principle, system, doctrine, theory", from the verbal root tan "stretch, extend, expand", and the suffix tra "instrument"), anglicised as tantrism or tantricism, is the name scholars give to a style of religious ritual and meditation that arose in medieval India no later than the fifth century CE, and which came to influence all forms of Indian religious expression to a greater or lesser degree.