Wiktionary
vb. (present participle of round up English)
Wikipedia
Rounding-up is a phenomenon that occurs in sailing when the helmsman (or tiller-handler) is no longer able to control the direction of the boat and it heads up (or "rounds up") into the wind, causing the boat to slow down, stall out, or tack. This occurs when the wind overpowers the ability of the rudder to maintain a straight course.
For example, the sailboat may heel over so far that the rudder no longer engages in the water, or only to such a small extent that it can no longer steer the boat. When this happens is dependent on a number of factors such as the velocity of the wind, design of the hull and rudder and shape of the sails. This can be dangerous if it causes collisions between boats if sailing close together. Rounding up can be startling to those on board: The boat turns into the eye of the wind with all sails fluttering. However, unless the boat is in irons (stopped facing directly into the wind), control can be regained by steering the boat off the wind again to refill the sails and regain the desired course. Rounding up is in fact a safety design of most sailboats that can help prevent a knock-down and allow the helmsman to regain control of the boat. An occasional round-up may simply be the result of a strong gust of wind. If it occurs regularly, this may be a sign that too much sail is raised and the crew may need to lower one or more sails, change to smaller sails, or reef. In smaller sailboats such as racing dinghies where the sail cannot be lessened or reefed, frequent round-ups may be a sign that the wind conditions are too strong for the boats and they should immediately proceed to shelter.
Usage examples of "rounding up".
The schooner was rounding up now and anchoring, and he saw the jolly boat returning from the Diamond with Southwick's rotund figure in the sternsheets.
Selquist drank a mug of ale with the Thane, just to be companionable, but as soon,as politely possible, he ditched the old fart and, rounding up his friends with a glance, left the Hall.
Chivvying Chuck back toward the party like a hen rounding up her chicks, the little old man steered Chuck around the towering wheels of the plane to where the others of his group now waited.
Ryba was checking over the mounts, and Istril headed off with two others to see about rounding up two mounts that had left the makeshift corral.
There was really nothing to do in St John's except to go ship-visiting and wait for the return journey: it was no more than a pause, in rough and simple terms, before making the outward passage of the narrows and rounding up the convoy again for its three-thousand-mile gauntlet, with the enemy ahead preparing new snares, brewing new poisons for their ruin.
Garnet split his men, sending one team down to the engine room and leading the other through the stern superstructure, rounding up the crew and making their way to the wheelhouse.
As he spoke, the three armed gunmen on the work deck began rounding up the survey ship's crew.
Even more important, perhaps, than rounding up food would be rounding up the civilian population.