sciomancy
/ˈsʌɪəmansi/noun
Divination through communication with the spirits of the dead.
- Often distinguished from necromancy in involving only the spirit, as opposed to the corpse, of a dead person..
Origin
Mid 16th century; earliest use found in William Painter (?1540–1594), translator and administrator. From post-classical Latin sciomantia from scio- + -mantia.