concave
🇺🇸
/kɑːnˈkeɪv/
🇬🇧
/kɒnˈkeɪv/
adjective
R
Shaped like the inside of a bowl or a cave, curving inward
The cave had a concave wall that echoed our voices.
洞穴有一面凹形的牆，它迴盪著我們的聲音。
translation
凹的