Bo·gey·man -- n. 

1.  Bogey (also bogy or bogie) is a Specter, a Phantom thought to be a source of annoyance, perplexity, or harassment.

2.  Bogeyman is a monstrous imaginary figure used to threaten children; a terrifying person or thing.

The Chichi Hoohoo Bogeyman by Virginia Driving Hawk Sneve, Nadema Agard

Psssst! It's Me...the Bogeyman by Barbara Park, Stephen Kroninger

El Cucuy : A Bogeyman Cuento in English and Spanish by Joe Hayes, Honorio Robledo