Muqarnas known in Iranian architecture as Ahoopāy (Persian: آهوپای) and in Iberian architecture as Mocárabe, is a form of ornamented vaulting in Islamic architecture. It is the archetypal form of Islamic architecture, integral to the vernacular of Islamic buildings.
Also known as honeycomb vaulting they come from the squinch and became popular in India too. The muqarnas below the balcony of the Qutub Minar would probably be the first introduction in India