bugaboo (chiefly American English)
noun

- an imaginary object of fear

- something that causes fear or distress out of proportion to its importance

(Merriam-Webster's Online Dictionary)

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WORD ORIGIN

Bugaboo belongs to a group of words that ultimately trace back to the Welsh word "bwg" (don't bother trying to pronounce it), which means hobgoblin or ghost. "Bwg" eventually evolved into the English "bug." As the Morris Dictionary of Word and Phrase Origins points out, "bwg" is one of the few Welsh words that made the transition to English. This is because the Welsh language is full of consonants.

The English "bug" held the same meaning as "bwg" for some time. Then -bear was added to make "bugbear," which is a scarecrow or hobgoblin in the form of a bear. The bugbear eventually came to signify a terrifying monster that was supposed to scare naughty children into being well behaved.

Other similar words developed over time, all of which relate to monsters, scary objects or fear in general. These include bogle (Scottish), bogey, bogeyman/boogeyman (English), boggart (supposedly originated in Yorkshire) and possibly barghest, a legendary monstrous black dog with huge teeth and claws (some claim that this is German in origin, Bär=bear + Geist= spirit or ghost).

Exactly where and how bugaboo evolved is unknown, but it is used mainly in American English to note something that creates an exaggerated or overstated sense of fear. By extension it is synonymous with an obstacle or impediment to progress.

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Practice OWAD in a conversation:

"Although the BUGABOO of unemployment is causing global concern, economies are resilient enough to recover."