A hobgoblin is a mischievous or troublesome spirit from old folklore, usually imagined as a small, ugly creature that plays pranks or causes minor problems. Unlike truly dangerous monsters, hobgoblins were thought to be more annoying than terrifying. They might hide your shoes, make milk spoil, or cause tools to mysteriously disappear, then reappear in odd places.

In medieval England, people blamed hobgoblins for everyday mishaps and unexplained troubles around the house or farm.

Today, we use hobgoblin to describe any persistent worry or fear that bothers us, even when it might not be truly dangerous. Ralph Waldo Emerson wrote that “a foolish consistency is the hobgoblin of little minds,” meaning that worrying too much about always being consistent can prevent creative thinking. If someone has a pet hobgoblin, they have a particular worry they can't let go of, like a student who constantly frets about being exactly on time even when arriving a minute late causes no real problem.

The word appears in fantasy games and stories, where hobgoblins are often depicted as larger, more warlike cousins of goblins.