Laughing is a wonderful thing, and there are so many ways to describe it. "Laugh ones head off" is a popular phrase that means to laugh uncontrollably, but there are plenty of other terms to express the same idea. For example, you could say someone is "doubling over with laughter," or that they're "chortling," "giggling," or "howling" with mirth. If someone is laughing and can't stop, you might say they're "in stitches" or "cracking up" with laughter. Whatever phrase you choose, laughter is a wonderful thing that brings joy and happiness to many people's lives.