Wikipedia
Wirry-cow
In Scotland, a wirry-cowe was a bugbear, goblin, ghost, ghoul or other frightful object. Sometimes the term was used for the Devil or a scarecrow.
The word was used by Sir Walter Scott in his novel Guy Mannering.
The word is derived by John Jamieson from worry ( Modern Scots wirry), in its old sense of harassment in both English and Lowland Scots, from Old English wyrgan cognate with Dutch wurgen and German würgen; and cowe, a hobgoblin, an object of terror.
Wirry appears in several other compound words such as wirry hen, a ruffianly character, a rogue; wirry-boggle, a rogue, a rascal; and wirry-carle, a snarling, ill-natured person, one who is dreaded as a bugbear.