Eldritch is a word that is rarely used today. An Old Middle English Word (thought to be of Scottish origin) first spoken in 1508, making it well over 500 years old, when the world was inhabited with ghosts and goblins and other-worldly creatures that roamed the Earth and couldn't be explained by us mere mortals, or at least was thought and believed to have roamed the Earth. A combination of Elf-riche, Elf or fairy and rich or abundant, an elf-kingdom so to speak. It means spooky or eerie.
An example in a sentence: Robert Louis Stevenson used the term eldritch, in his 1886 novel 'Kidnapped'
"whose voice had risen to a kind of eldritch sing-song, turned with a skip, and was gone."
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