fall line(redirected from Gnat line)
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1. The steepest possible line of descent from a given point on a slope.
2. A line connecting the waterfalls of upland rivers before they reach a common coastal plain, often marking the limit of upstream navigation and indicating a zone of potential water power for industrial purposes.
1. (Skiing) skiing the natural downward course between two points on a slope
2. (Physical Geography) the edge of a plateau
(Placename) a natural junction, running parallel to the E coast of the US, between the hard rocks of the Appalachians and the softer coastal plain, along which rivers form falls and rapids
1. the natural boundary between an upland and a lowland, as a piedmont and a coastal plain: marked, in temperate or humid areas, by waterfalls and rapids.
2. Skiing. the path of natural descent from one point on a slope to another.
Most direct route to the bottom of a slope.