Used to express a lack of patience when you're eager to start something or get somewhere. I'm antsy to begin our trip; I've packed everything hours ago!
Pro Tip 2/3
Not Formal
'Antsy' is informal, more suitable for casual conversations than formal writing or speaking. During family dinners, the kids get antsy sitting at the table for too long.
Pro Tip 3/3
Subtle Anxiety
'Antsy' often implies a mild, underlying anxiety, rather than overt distress. I always get a little antsy before job interviews.