floodgate, n.
1 a gate opened or closed to admit or exclude water, esp. the lower gate of a lock.
2 (usu. in pl.) a last restraint holding back tears, rain, anger, etc.

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THESAURUS

floodgate

aboideau, air lock, avenue, blowhole, channel, chute, debouch, dock gate, door, egress, emunctory, escape, estuary, exhaust, exit, flood-hatch, flume, gate, head gate, lock, lock gate, loophole, opening, out, outcome, outfall, outgate, outgo, outlet, penstock, pore, port, sally port, sluice, sluice gate, spiracle, spout, tap, tide gate, vent, ventage, venthole, vomitory, water gate, way out, weir

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ROGET THESAURUS

floodgate

Limit

N limit, boundary, bounds, confine, enclave, term, bourn, verge, curbstone, but, pale, reservation, termination, terminus, stint, frontier, precinct, marches, backwoods, boundary line, landmark, line of demarcation, line of circumvallation, pillars of Hercules, Rubicon, turning point, ne plus ultra, sluice, floodgate, definite, conterminate, conterminable, terminal, frontier, bordering, thus far, thus far and no further, stick to the reservation, go beyond the pale, Special.

Egress

N egress, exit, issue, emersion, emergence, outbreak, outburst, eruption, proruption, emanation, egression, evacuation, exudation, transudation, extravasation, perspiration, sweating, leakage, percolation, distillation, oozing, gush, outpour, outpouring, effluence, effusion, effluxion, drain, dribbling, defluxion, drainage, outcome, output, discharge, export, expatriation, emigration, remigration, debouch, debouche, emunctory, exodus, emigrant, outlet, vent, spout, tap, sluice, floodgate, pore, vomitory, outgate, sally port, way out, mouth, door, path, conduit, airpipe, effused, outgoing.

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