Necrophobia or thanatophobia is the fear of death or dead things (e.g., corpses) as well as things associated with death (e.g., coffins). The former term is derived from Greek nekros for "corpse" and -phob- for "fear". The latter term is derived from Thanatos (θάνατος: "death"), the personification of death. The usage differs, although in common speech the terms are used interchangeably. Thanatophobia does include but is not limited to the fear of personal death or dying.