soma, psychotropic plant, the juice of which was sometimes drunk as part of the Vedic sacrifice (see Veda). Many hymns in the Rig-Veda are in praise of soma. In the late Vedic period substitutes for soma came to be used, and the original plant was lost. It has recently been identified with the fly agaric mushroom, Amanita muscaria, used in Siberian shamanism.

In ancient Indian religion, an unidentified plant, the juice of which was an offering of the Vedic sacrifices. Its stalks were pressed, and its juice, filtered through wool, was mixed with water and milk. After being offered as a libation to the gods, the remainder of the soma was consumed by the priests and the sacrificer. It was highly valued for its exhilarating, probably hallucinogenic, effect. The plant was believed to have been delivered to the earth from heaven by an eagle. The personified deity Soma was the master of plants, healer of disease, and bestower of riches. Seealso Vedic religion.

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