E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Bugbear.
A scarecrow. Bug is the Welsh bwg, a hobgoblin, called in Russia buka. Spenser says, A ghastly bug doth greatly them affear (book ii. canto 3); and Hamlet has bugs and goblins (v. 2).
1
Warwick was a bug that feared us all.
Shakespeare: 3 Henry IV., v. 3.
To the world no bug bear is so great
As want of figure and a small estate.
Pope: Satires, iii. 6768.
The latter half of this word is somewhat doubtful. The Welsh bár = ire, fury, wrath, whence barog, spiteful, seems probable.