Before revision: 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 or stall out .
After revision: 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 or gybe .