Elfshot is an old word used to describe a mysterious phenomenon that people thought was caused by elves! Back in the olden days, people believed that mischievous elves would shoot you with invisible arrows, causing you to feel sick or have aches and pains.
But nowadays, we know that elfshot isn't caused by elves at all. In reality, it's probably caused by something else entirely, like maybe a lightning strike, a muscle strain, or an insect bite.
Although it's not something that is commonly talked about these days, elfshot is still an interesting part of folklore and an example of how people used to explain things they didn't understand. So while it may not be a real thing, it's still pretty cool to learn about!