A severe facade rose above this door; a wall, perpendicular to the facade, almost touched the door, and flanked it with an abrupt right angle.

大门的上方便是那房屋的正面，气象庄严，一道和房屋正面垂直的墙紧靠在大门旁边，构成一个生硬的直角。

youdao

Non-radial Imperfection. A non-radial imperfection may be defined as any imperfection whose vertical axis is not perpendicular (it's at an angle) to the material surface.

非径向缺欠。非径向缺欠可定义为其纵轴不垂直于（存在一个角度）材料表面的任何缺欠。

youdao

Well, at point P, the velocity vector QP is perpendicular to the line QP, 1 so the sine of that angle is one.

点P，速度向量,垂直于直线，所以该角的正弦值为。

youdao

The severity of the laboratory test was equivalent to an oblique collision with the rocky surface of the Earth - a comet coming in at an angle of less than 25 degrees from the horizon, rather than head on (perpendicular to the Earth's surface).

BBC: Comets could have seeded life on Earth