floodgate
🇺🇸
/ˈflʌdɡeɪt/
🇬🇧
/ˈflʌdɡeɪt/
A door to stop or let water go through in a river.
Opening the floodgate helped prevent the town from flooding.
打开防洪门有助于防止小镇洪水泛滥。