Pertaining to the apex or top; at or in the zenith; straight overhead.

绝顶的；顶端的；在顶点的；正在头顶上的。

At right angles with the horizon; upright.

垂直的；直立的。

Of or pertaining to a vertex.

顶点的。

A line, plane, or circle at right angles with the horizon.

垂直线；垂直面；垂直圆。