dome

dome
/dəum; dom/ n
1 rounded roof with a circular base 穹顶; 圆屋顶
    the dome of St Paul's cathedral 圣保罗大教堂的穹顶.
2 thing shaped like this 圆顶形物; 穹形物
    the dome of a hill, the night sky, a bald head 山包、 黑夜的天穹、 光秃的头顶.

牛津英汉双解词典