-truncated-

a. 1. Cut off; cut short; maimed. [ 1913 Webster ]

2. (Min.) Replaced, or cut off, by a plane, especially when equally inclined to the adjoining faces; as, a truncated edge. [ 1913 Webster ]

3. (Zool.) Lacking the apex; -- said of certain spiral shells in which the apex naturally drops off. [ 1913 Webster ]

Truncated cone or
Truncated pyramid (Geom.), a cone or pyramid whose vertex is cut off by a plane, the plane being usually parallel to the base. [ 1913 Webster ]