tetarto-
(tɪˈtɑːtəʊ)
combining form of Gr. τέταρτος fourth (cf. tetra-), in scientific terms belonging chiefly to crystallography. teˌtartoˈhedral a. [Gr. ἕδρα base], having one fourth of the number of faces required by the highest or holohedral degree of symmetry belonging to its system; hence teˌtartoˈhedrally adv., in a tetartohedral manner. teˌtartoˈhedric, -ˈhedrical adjs., = tetartohedral. teˌtartoˈhedrism, the property or quality of crystallizing in tetartohedral forms; the condition in which a crystal symmetrically develops only one fourth of the number of planes demanded by holohedral symmetry. teˌtartoˈhedron, a tetartohedral crystal. teˌtartoˈhedry, = tetartohedrism. teˌtartoheˈxagonal a., having one quarter of the number of normals belonging to the hexagonal system. teˌtartoprisˈmatic a., teˌtartoˈpyramid: see quots. teˌtartosyˈmmetric, -syˈmmetrical adjs.: see quot. teˌtartoˈsymmetry, a variety of merosymmetry, in which only one fourth of the faces of the holosymmetrical form are retained. teˌtartosysteˈmatic a., said of a form in which only one fourth of the origin-planes are extant.
| 1858 Dana Min. (ed. 4) 49 They are *tetartohedral forms, or contain only one-fourth the number of planes occurring under complete symmetry. 1864 Watts Dict. Chem. II. 144 Quartz likewise exhibits other forms of tetartohedral development. 1888 Rutley Rock-Forming Min. 64 The development of certain plagihedral, or tetartohedral, faces. |
| 1864 Webster, *Tetartohedrally. |
| 1854 Pereira's Pol. Light 234 Doubly oblique prismatic system..or the *tetartohedric-rhombic system. |
| 1860 Mayne Expos. Lex., *Tetartohedrical. |
| 1858 Dana Min. (ed. 4) 49 A form of this kind..is found in Titanic Iron, and is called rhombohedral *tetartohedrism. 1895 Story-Maskelyne Crystallogr. 160 The ambiguity in which the terms hemihedrism, tetartohedrism, etc. are involved. |
| Ibid. 231 There can only be a single kind of *tetartohedron in the Cubic system. |
| 1864 Watts Dict. Chem. II. 144 *Tetartohedry. Quartz affords a remarkable example of a combination in which only one-fourth of the possible faces are present. |
| 1895 Story-Maskelyne Crystallogr. 284 Six faces corresponding to three normals: *tetarto-hexagonal diplohedral forms. Three faces corresponding to three normals: tetarto-hexagonal haplohedral forms. |
| 1847 Webster, *Tetartoprismatic,..one fourth prismatic, applied to oblique rhombic prisms.—Mohs. 1851 Richardson's Geol. v. (1855) 98 Classification of Mohs..V. The Tetarto-Prismatic is composed of the oblique rhomboidal prism. |
| 1891 Cent. Dict., *Tetartopyramid,..a quarter-pyramid: said of the pyramidal planes of the triclinic system, which appear in sets of two (that is, one fourth the number required by a complete pyramid). |
| 1895 Story-Maskelyne Crystallogr. 159 Mero-symmetrical forms may be hemi-symmetrical..*tetarto-symmetrical, presenting one-quarter only of the faces of the holo-symmetrical form. |
| Ibid. 160 *Tetarto-symmetry, where the form is (i) hemi⁓systematic and haplohedral, (ii) *tetarto-systematic and diplohedral. Ibid. 308 Tetarto-systematic haplohedral forms. |
b. Path. ‖ tetartoˈphyia [
Gr. ϕυή growth], a remitting quartan fever.
| 1857 Dunglison Dict. Med. Sc., Tetartophia,..a quartan, in which the intermission is inordinately short or imperfect. 1895 Funk's Stand. Dict., Tetartophyia. |