Sailing

The fifteenth entry is la deriva mobile, and the adjective is doing more work than it looks. La deriva on its own is the sideways slip a hull makes when the wind pushes it across its own course, which English calls « leeway » or simply « drift ». From there the Italian word moved to the thing that prevents it: the plate lowered through the bottom of a small boat, which English names « the centreboard » when it swings on a pivot and « the daggerboard » when it drops straight down. Hence mobile, movable, because a fixed one is la deriva fissa. Then the word moved once more, to the boat itself: una deriva is a dinghy, a light centreboard boat, as against one held upright by a ballasted keel. A single noun therefore carries the fault, the cure and the vessel, and only the sentence around it says which is meant. The everyday sense goes on living beside all three, since andare alla deriva is to drift, of a boat and of a person alike, and that is the one place where English keeps the same picture.