Mercifully means in a way that shows mercy or compassion, sparing someone from suffering or difficulty. When a test is mercifully short, the teacher has kindly kept it brief instead of making it long and exhausting. When a boring speech is mercifully interrupted by the fire alarm, everyone feels relieved to escape.

The word comes from mercy, which means compassion or forgiveness toward someone you have power over. When something happens mercifully, it brings relief from something unpleasant. A dentist might work mercifully quickly so a patient doesn't have to sit in the chair very long. A coach might mercifully end practice early on a scorching hot day.

You'll often see this word used with a touch of humor or exaggeration. If someone says a movie was mercifully short, they're suggesting it wasn't very good, so at least it ended quickly. The word captures that feeling of gratitude when something difficult or uncomfortable finally ends, or when someone shows unexpected kindness by making a hard situation easier.