Height, in elementary geometry
The segment of the perpendicular dropped from a vertex of a geometric figure (a triangle, a pyramid, a cone) on its base or on its extension, and also the length of this segment.
The height of a trapezium, prism, cylinder, spherical segment, or a pyramid or a cone truncated parallel to the base, is the distance between the lower and the upper base. The figure shows the heights $h$ of a triangle, of a trapezium and of a truncated cone.
Height, in elementary geometry. Encyclopedia of Mathematics. URL: http://www.encyclopediaofmath.org/index.php?title=Height,_in_elementary_geometry&oldid=32892