物体是凹的是指至少存在两个物体内部的点其连线不能完全包含在物体内部反义词为凸
An object being concave means that there are at least two points inside the object, and the line connecting them cannot completely cover the interior of the object. The antonym is convex
以上为机器翻译结果，长、整句建议使用 人工翻译 。