A traditional African healer. Occasionally used of people supposed to possess malign powers.
Late 19th century; earliest use found in John Mackenzie (1835–1899), missionary in Africa. From Southern Sotho, Northern Sotho, and Tswana ngaka doctor, healer, herbalist, traditional doctor known for powers of witchcraft, of uncertain origin. Probably related to verb stem -ngaka to be constipated, curb.