Bugaboo; Bugbear

Part of speech: noun (n.)

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

Synonyms: Hobgoblin; goblin; specter; ogre; scarecrow.