fall behind in (something)(redirected from fallen behind in)
fall behind in (something)
1. To not be as current with some task as one should or ideally would be. I fell behind in my schoolwork when I had the flu.
2. To move or act more slowly than someone else. I fell behind her early in the race and could just never catch up.
3. To not be able to satisfy one's current financial obligations. All of those medical bills have caused me to fall behind in the rent.