A job you take knowing that it isn't long term. Often due to an emergency situation where you know your losing your current job. It provides a paycheck while you take your time looking for a better job.

When you eat dirt for the first time and leave your family to build a shack in the woods

A job you take when you've recently lost or feel you are about to lose another (usually better) job. The rebound job is likely not in one's chosen career path, and often its only purpose is for the worker to earn money while searching for a more suitable (better paying/career-advancing) position.