meself, is "bugaboo" the word you're thinking of?

I found this information online http://www.mootgame.com/ballast/bal108.html and wonder if it's accurate:

"The Welsh name for the Devil, Bwcibo, entered English centuries ago. What word did it evolve into?

Answer: bugaboo

A devil is a bugaboo. Though its etymology is uncertain, the word bogey was probably originally a proper name for the devil."