platband

From plat +‎ band.

platband (plural platbands)

1. A border of flowers in a garden, especially along a wall; a strip of turf forming a border.
2. (figuratively) Any border.
3. (architecture) A flat fascia on an architrave, or forming a border round a window, or a horizontal band along a wall.
4. (architecture) A fillet on a column, between the flutings.
5. (rare) A flat lintel over a door or window.