black border; mourning border
A black border used on obituaries, funeral notices, or memorial items to indicate mourning. Also used more generally for any black frame or border.
The obituary has a black border.
写真に黒枠を付けて飾った。
I framed the photo with a black border and displayed it.
Compound of 黒 (くろ, 'black') and 枠 (わく, 'frame, border').