Truncated

ppl. a. [f. L. truncāt-us, pa. pple. of truncāre (see prec.) + -ED¹ 2, or f. prec. + -ED¹.] Cut short (actually or apparently); having a part cut off, or of such a form as if a part were cut off.

  1.  Her. Of a cross or tree: Having the arms or boughs cut off, so as not to extend to the boundaries of the shield; couped. ? Obs.

1486.  Bk. St. Albans, Her., C vj b. A cros truncatid, And hit is calde trunkatid for hit is made of ij treys the boys [= boughs] cut a Way.

1572.  Bossewell, Armorie, II. 95 b. These trees are truncated, that is to saie, ye boughes cut of from the body, and laide in the forme of a Saltier. The endes whereof may not touch the Angles of the shield.

  2.  In modern scientific and technical use. (Const. as adj. preceding the noun, or as pa. pple. following the noun.) a. Geom., etc. Of a figure: Having one end cut off by a transverse line or plane; esp. of a cone or pyramid: Having the vertex cut off by a plane section, esp. one parallel to the base: thus truncated cone or pyramid = FRUSTUM of a cone or pyramid.

1704.  J. Harris, Lex. Techn., I. Truncated Pyramid or Cone, is one whose top is cut off by a Plane parallel to its Base; and therefore the Figure of the truncated top must always be similar to the Base.

1827.  Faraday, Chem. Manip., ii. (1842), 26. Weights … constructed in sets, each weight … having the form of a truncated cone.

1831.  R. Knox, Cloquet’s Anat., 581. The Cartilages of the apertures of the Nose … represent an ellipse truncated posteriorly.

1840.  Lardner, Geom., 68. A trapezium is a truncated triangle. Ibid., 166. A figure formed by the section of a prism by a plane not parallel to its base is called a truncated prism.

1868.  Lockyer, Guillemin’s Heavens (ed. 3), 73. The southern horn of the crescent was truncated.

  b.  Cryst. and Solid Geom. Of an edge or solid angle: Cut off or replaced by a plane face, esp. one equally inclined to the adjacent faces; also said of a solid figure having its edges or angles thus cut off.

1796.  Kirwan, Elem. Min. (ed. 2), I. 128. [Fluor] the angles or edges rarely truncated or bevilled.

1823.  H. J. Brooke, Introd. Crystallogr., 24. When an edge, or solid angle, is replaced by one plane, it is said to be truncated. When an edge is replaced by two planes, which respectively incline on the adjacent primary planes at equal angles, it is bevilled.

1863.  Geo. Eliot, Romola, xxvi. The wide doorway, standing at the truncated angle of a great block … of houses.

1875.  Bennett & Dyer, trans. Sachs’ Bot., 51. The separate crystalloids are thin plates, single regular rhombs, often with truncated angles.

1891.  Cent. Dict., s.v. Truncate v., Truncated cube, cuboctahedron, dodecahedron [etc.].

  c.  Nat. Hist. Appearing as if the tip or end were cut off transversely; terminating in a flat or broad edge or surface instead of a point.

1752.  J. Hill, Hist. Anim., 3. The Enchelis, with the head small, and the tail truncated.

1753.  Chambers, Cycl. Supp., s.v. Leaf, Truncated Leaf, that whose summit or point seems to have been cut off, or is terminated by a strait line in a transverse direction.

1816.  Stephens, in Shaw, Gen. Zool., IX. II. 236. Quills dusky black; the points … truncated.

1835.  J. Duncan, Beetles (Nat. Libr.), 184. The elytra are short and truncated at the extremity.

1899.  Allbutt’s Syst. Med., VIII. 774. These truncated hairs are of … importance for diagnosis.

  d.  So in Architecture, Geology, etc.

1723.  Chambers, trans. Le Clerc’s Treat. Archit., I. 114. Pediments … supported by an Entablature truncated in the middle.

1727–41.  Chambers, Cycl., s.v. Roof, Sometimes it is truncated; that is, instead of terminating in a ridge or angle, it is cut square off at a certain heighth.

1829.  Scott, Anne of G., xi. A truncated column of marble, having its base sculptured with hieroglyphical imagery.

1830.  Lyell, Princ. Geol. (1872), I. II. xxiii. 588. The summit of the loftiest peak is truncated.

1869.  Boutell, Arms & Arm., ii. (1874), 11. In some [Assyrian] examples, the raised upper crest-like part of the helm is seen to have been bent backwards and truncated.

  3.  Maimed, mutilated; also fig.

1731.  Bailey, Truncated, cut shorter, maimed, mangled.

1791–1823.  D’Israeli, Cur. Lit. (1858), III. 181. All the Italian editions continued to be reprinted in the same truncated condition.

1845.  R. W. Hamilton, Pop. Educ., v. (ed. 2), 97. The truncated frame of man is without power of locomotion or external action.

1890.  J. Stalker, Imago Christi, v. (1891), 104. It is a truncated and most imperfect friendship when this region is closed.