More strange, frightening, or mysterious; comparative form of eerie.
From eerie (from Middle English 'erie' or 'eary', possibly from Old English 'earg' meaning cowardly or timid) plus the comparative suffix -er. The 'ee' spelling became standard by the 1800s.
The word eerie might come from an old word for cowardice—so something eerie is literally something that makes you feel cowardly or afraid, which is why it perfectly describes that creepy feeling!
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