What was the Inca Empire's name in Quechua?

The Inca Empire was called Tawantinsuyu in Quechua.

The name Tawantinsuyu means something like “the realm of the four parts.” It combines Quechua terms associated with four and with regions or provinces joined into a larger whole. The name reflected the empire’s political organization around Cusco, its capital, from which four great suyu extended across the Andes.

Those four regions were Chinchaysuyu to the north, Antisuyu to the east, Qullasuyu to the south, and Kuntisuyu to the west. The names of the wrong options are therefore not alternative names for the empire: they are names of individual quarters within it. Spanish writers also recorded the name in forms such as Tahuantinsuyo or Tahuatinsuyo.

The familiar expression “Inca Empire” became common through Spanish and later modern usage. In Quechua contexts, Tawantinsuyu better captures the state’s own geographic and political conception. The empire expanded rapidly under rulers including Pachacuti during the fifteenth century and was conquered by the Spanish in the sixteenth.