フォールライン

noun

fall line

A skiing term referring to the line of steepest descent down a slope. Also used in geography for the line connecting points where rivers drop from uplands to lowlands, but the skiing sense is more common in Japanese.

• スキーでは、フォールラインに沿そって滑すべると最もっとも速はやく降おりられる。

  In skiing, following the fall line allows you to descend the fastest.