- Nominal governance by a dead person, through posthumous holding of an official position of authority, or by popular veneration and lasting influence of a personal ideology.
- The enactment of mass and organized killing as an official policy of a state.
- The enactment of policies held to lead, directly or indirectly, to death or an increased risk of death.
- A culture in which rituals relating to the dead play a unique or important role.
- (figuratively) Endemic stagnation or decay.
From Greek thanato-, "death", and -cracy, "rule".