Ushnisha

The ushnisha (Sanskrit, n., _sa. उष्णीष, IAST|uṣṇīṣa) is a bump at the top of the head of the Buddha. It symbolizes his wisdom and openness as an enlightened being.

The ushnisha was not described initially in the Physical characteristics of the Buddha spelled out by the Buddhist canon. Rather, there are several mentions about a topknot::"His topknot is like a crown." (Secondary characteristics, No53):"He has a topknot as if crowned with a flower garland." (Secondary characteristics, No80)

The first representations of the Buddha in the 1st century CE in the Greco-Buddhist art of Gandhara also represent him with a topknot, rather than just a cranial knob. It is thought that the interpretation of the ushnisha as a supernatural cranial protuberance happened at a later date, as the representation of the topknot became more symbolized and its original meaning was lost (Mario Bussagli, "L'art du Gandhara").