An intention is idea that you plan (or intend) to carry out. If you mean something, it's an intention.
Your goal, purpose, or aim is your intention. It's something you mean to do, whether you pull it off or not. You may have the best intention of cooking an incredible meal, but if you leave the burner on and burn the house down, you will not be remembered as an excellent chef. When a father asks his daughter's boyfriend "What are your intentions?" that means something specific: Does he want to marry her?