Sumo Ring
noun
On the soil we put straw sacks in a circle to mark a sumo ring. Go look up some pictures of this word in Japanese and you'll see exactly what we mean. Better yet, go see some live sumo!
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
誰かが土俵にパンの欠片を投げ込みました。
Someone threw a piece of bread into the sumo arena.