To flood out somebody (or flood somebody out) is to force them to leave their business or home because of floods.
Example of use:
1. There was a torrential downpour last night and we were flooded out. The house is a mess and we’re staying in a hotel for a few days.
2. Every time it rains heavily the river rises and floods them out.
infinitive – flood out
present simple – flood out and floods out
-ing form – flooding out
past simple – flooded out
past participle – flooded out
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