featheredge

noun

1. an edge that thins out like a feather.
2. the thinner edge of a wedge-shaped board or plank.
3. a tool for giving a smooth, even finish to plasterwork at corners.
4. (in silver work) a band of closely spaced oblique lines engraved along an edge of a piece.

noun

1. a board or plank that tapers to a thin edge at one side