When you are hungry but you don’t know exactly what you want to eat or what you are in the mood for.
An amalgam of hungry and unsure invented to describe that feeling when you want to eat something and you are very hungry but nothing sounds particularly good to you or too many things sound really good to you and you can’t decide which thing you should eat.
“Q: what are you doing for lunch? A: I’m hunsure” or
“I’m hunsure, can you help me decide what I want?”