The word “nightmare” on the other hand comes from the Old English word “mare”. It is said to be a mythological demon or goblin who tortures other beings with horrifying dreams. The prefix “night-“ was later added to give emphasis to the dream-aspect. The whole word itself is related with the older German term Nactmahr.

Interpreting dreams and nightmares dates back to a more historical period wherein Egyptians, Greeks and Romans believed that dreams merely visits from their gods and that these dreams only have a divine interpretation. For the Egyptians, dreams were comparatively straightforward and were but an insight of things that exists, but cannot be seen or heard in real life. The Egyptians would try to contact their dream world by performing rituals and incantations, and would try to summon “spirits” from within. They believe that contact with these spirits would bring signs of warnings, guidance, recovery from illnesses, or would simply bring pleasurable experiences. The Greeks saw this as a way of understanding messages from the gods. In Greek mythology, Hypnos, who was known as the god of sleep, would let his son Morpheo, bring dreams to human being while they slept. Making sacrifices and offering gifts to the gods whom they wish to convey in their dreams were expected from them. Dreaming was also a procedure for them to cure illnesses, in which a god would appear in their dreams and would indicate the remedy.