The Collaborative International Dictionary
Downhaul \Down"haul`\ (doun"h[add]l`), n. (Naut.) A rope to haul down, or to assist in hauling down, a sail; as, a staysail downhaul; a trysail downhaul.
Wiktionary
n. (context nautical English) Any rope used to haul down a sail or spar
Wikipedia
The downhaul is a line which is part of the rigging on a sailboat; it applies downward force on a spar or sail. The most common downhaul on a modern sailboat is attached to the spinnaker pole, though this may be referred to as the foreguy in some rigging nomenclature. The term is also commonly applied to the cunningham on the mainsail.
In a windsurfing rig, the downhaul is the primary load-bearing line which controls the sail's shape. Modern windsurfing sails incorporate a sleeve for the mast, and therefore do not have a halyard which tensions the top of the sail. The downhaul is tensioned early in the rigging process and is generally not adjustable on the water, and is therefore rather different in use than the downhaul on a sailboat.
Usage examples of "downhaul".
All hands obeyed, and at once the eight or ten seamen who composed the crew, sprang to their respective stations at the spanker brails and outhaul, topsail sheets and halyards, the jib downhaul, and the topsail clewlines and buntlines.
I remember one day in a reefing job, the downhaul parted and came do on deck from the peak of the spanker.
When the weather moderated, and we shook the reefs out, the downhaul was forgotten until we happened to think we might soon need it again.
One of those Benton boys was at the wheel, and before I knew what he was doing, the other was out on the gaff with the end of the new downhaul, trying to reeve it through its block.
I coiled down the mizzen-topsail downhaul myself, and was going aft to see how she headed up, when I stopped to look at a light, and leaned against the deck-house.
It was blowing now, and it was all that I and two others could do to get in the slack of the downhaul, while the others lowered away at the peak and throat, and we had our hands full to get a couple of turns round the wet sail.
And, boy, did they know from tack downhaul, kicking strap, mainsheet, clew outhaul, topping lift, boom, tack, reefing points, leech, spreader, foresail hanks, shrouds, inner forestay, stanchion, toe rail, and fin keel!
We learn about booms and mainsheets and downhauls and the parts of the sail and how to hold the tiller and tuck the sail in just so, which I think is just fine till one day Tink and I are out in a boat with about ten seamen, which is going into a small deserted cay to look for fresh water.