truncatingadj. that truncates; spec. said of a plane that replaces an edge or solid angle.
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the world > space > extension in space > measurable spatial extent > longitudinal extent > shortness > [adjective] > shortened > shortening as if by cutting
truncating1805
1805 R. JamesonTreat. External Characters Minerals 43 The direction of the truncating planes..is either rectilinear, curvilinear, or rounded off.
1882 J. RuskinBible of Amiens iii. 95 These two truncating and guarding rivers.