Something frightful, as a specter; anything imaginary that causes needless fright; something used to excite needless fear; also, something really dangerous, or an imaginary monster, used to frighten children, etc. "Bugaboos to fright ye." "But, to the world no bugbear is so great As want of figure and a small estate." "The bugaboo of the liberals is the church pray." "The great bugaboo of the birds is the owl."
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