asura, in Hindu mythology, class of beings defined by their opposition to the devas or suras (gods). The term asura appears first in the Vedas, a collection of poems and hymns composed 1500–1200 bce, and refers to a human or divine leader. Its plural form gradually predominated and came to designate a class of beings opposed to the Vedic gods. Later the asuras came to be understood as demons. This pattern was reversed in Iran, where ahura came to mean the supreme god and the daevas became demons. In Hindu mythology, the asuras and the devas together sought to obtain amrita (elixir of immortality) by churning the milky ocean. Although they had agreed to share the amrita, strife broke out over its possession, which led to a never-ending conflict.