The Sanskrit term ""vajra"" denoted a thunderbolt like a legendary weapon and divine attribute that was made from an adamantine, or an indestructible substance which could, therefore, pierce and penetrate any obstacle or obfuscation. It is the weapon of choice of Indra, the King of the Devas. As a secondary meaning, "vajra" symbolizes the ultimate nature of things which is described in the tantras as translucent, pure and radiant, but also indestructible and indivisible. It is also symbolic of the power of tantric methods to achieve its goals.