1. Of a liquid, to move quickly out of something. I pulled out the stopper, causing water to flood out of the bathtub.

2. To move quickly out of some place or thing in large numbers. As soon as the dismissal bell rang, kids began flooding out of the school building.

3. To cause someone or something to leave or flee some thing or place. In this usage, a noun or pronoun is used between "flood" and "out." High tide flooded us out of our tent. I suspect that the rains have flooded many animals out of their burrows.