floodgate

An adjustable gate or valve used to control the flow of water through a sluice.

At the start of the Second World War floodgates would be installed at the ends of the under-Thames sections of the Bakerloo and Northern lines to save them from inundation should bombs damage the riverbed.

Anything that controls or limits an outpouring of people, emotion, etc.

“The floodgates for advertising on cable are down,” says Michael Dann, a leading consultant on cable television.

A stream that passes through a floodgate; a torrent.

Out of her gored wound the cruell ſteel / He lightly ſnatcht, and did the floodgate ſtop / VVith his faire garment: then gan ſoftly feel her feeble pulſe, to proue if any drop / Of liuing blood yet in her veynes did hop

The accuſation conſiſting of thoſe three articles, was moſt true: your doctrine was ſcādalous, it offred much offence, being generally diſtaſted; and was erroneous, being detected to be the floodgate of Traitors ſtaiers, looſing in ſome ſuppoſititious doctrines, and many blaſphemous arrogating much to man, derogating much from God.

A series of allegations of corruption, mismanagement, and irregularities in flood control projects in the Philippines during and before the administration of President Bongbong Marcos.