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