n.洞；空穴；腔；蛀洞

I have a toothache because there is a cavity in one of my teeth. 我牙疼，因?yàn)槲业囊活w牙齒上有個(gè)洞。

He jammed the material in until the cavity was full. 他用力把材料塞進(jìn)去，直到空穴完全填滿。

The peritoneal cavity is a closed sac. 腹膜腔是一個(gè)封閉的囊腔。

The tumor growing in the enteric cavity blocked excretion of food. 腫瘤在腸腔里生長(zhǎng)阻礙了食物排泄。

n.中央凹陷；凹洼；凹狀

adj.兩面凹的