necromancy (NEK-ruh-man-see) noun
1. Divination by trying to communicate with the spirits of the dead.
2. Magic; sorcery; witchcraft.
[From Greek nekros (corpse) + -mancy (divination). Ultimately from Indo-European root nek- (death) that's also the source of nuisance,obnoxious, pernicious, innocent, innocuous, nectar, and nectarine.]
Before the word arrived in its current form, it was known as nigromantia in medieval Latin, from confusion of Greek nekro with Latin niger (black). Now you know why magic and sorcery are also known as the "black arts".
"A few years later, [Branaghstein] goes to university to study medical science, with a minor in necromancy."
-- Desson Howe; Creature Discomforts; The Washington Post; Nov 4, 1994.