bloodcurdling

adj

1. Causing great horror or terror.

   “Out of nowhere, in the middle of the night, came a bloodcurdling scream.”

   “Yet the old-time fairy tale, having served for generations, may now be classed as “historical” in the children’s library; for the time has come for a series of newer “wonder tales” in which the stereotyped genie, dwarf and fairy are eliminated, together with all the horrible and bloodcurdling incident devised by their authors to point a fearsome moral to each tale.”