Other forms: hellions
A hellion is someone who makes mischief or gets into trouble. You might refer to the kids you babysit as a bunch of hellions if they regularly refuse to go to bed, instead staging massive pillow fights.
Hellion almost always describes a young person, often a child, who raises a ruckus or makes trouble in some rowdy way. The little boy next door might have most people fooled into thinking he's an angel, but you'll know he's a hellion when you spot him jumping off the roof into a pile of snow or putting firecrackers in your mailbox. Hellion is an American word, inspired by the Scottish hallion, or "scamp."