Real Dictionary

seance
countable noun: A seance is a meeting in which people try to make contact with people who have died.

séance in American English
a meeting or session; now specif., a meeting at which a medium seeks to communicate with the spirits of the dead
noun: a meeting in which a spiritualist attempts to communicate with the spirits of the dead

seance in British English
noun: a meeting at which spiritualists attempt to receive messages from the spirits of the dead