a. [ Gr. brachy`s short + E. diagonal. ] Pertaining to the shorter diagonal, as of a rhombic prism. [ 1913 Webster ]

Brachydiagonal axis, the shorter lateral axis of an orthorhombic crystal. [ 1913 Webster ]

n. The shorter of the diagonals in a rhombic prism. [ 1913 Webster ]

n. [ Gr. kli`nein to incline + E. diagonal. ] (Crystallog.) That diagonal or lateral axis in a monoclinic crystal which makes an oblique angle with the vertical axis. See Crystallization. -- a. Pertaining to, or the direction of, the clinodiagonal. [ 1913 Webster ]

a. Pertaining to a decagon; having ten sides.

a. [ L. diagonalis, fr. Gr. &unr_; from to angle; dia` through + &unr_; an angle; perh. akin to E. knee: cf. F. diagonal. ] (Geom.) Joining two not adjacent angles of a quadrilateral or multilateral figure; running across from corner to corner; crossing at an angle with one of the sides. [ 1913 Webster ]

Diagonal bond (Masonry), herringbone work. See Herringbone, a. --
Diagonal built (Shipbuilding), built by forming the outer skin of two layers of planking, making angles of about 45° with the keel, in opposite directions. --
Diagonal cleavage. See under Cleavage. --
Diagonal molding (Arch.), a chevron or zigzag molding. --
Diagonal rib. (Arch.) See Cross-springer. --
Diagonal scale, a scale which consists of a set of parallel lines, with other lines crossing them obliquely, so that their intersections furnish smaller subdivisions of the unit of measure than could be conveniently marked on a plain scale. --
Diagonal stratification. (Geol.) Same as Cross bedding, under Cross, a. [ 1913 Webster ]

n. 1. A right line drawn from one angle to another not adjacent, of a figure of four or more sides, and dividing it into two parts. [ 1913 Webster ]

2. (Engin.) A member, in a framed structure, running obliquely across a panel. [ 1913 Webster ]

3. A diagonal cloth; a kind of cloth having diagonal stripes, ridges, or welts made in the weaving. [ 1913 Webster ]

adj. (Math.) able to be diagonalized; -- of a matrix. [ PJC ]

v. t. (Math.) to transform a matrix to a diagonal matrix. [ WordNet 1.5 ]

adv. In a diagonal direction. [ 1913 Webster ]

a. [ Pref. di- + hexagonal. ] (a) Consisting of two hexagonal parts united; thus, a dihexagonal pyramid is composed of two hexagonal pyramids placed base to base. (b) Having twelve similar faces; as, a dihexagonal prism. [ 1913 Webster ]

a. (Geom.) Belonging to an enneagon; having nine angles. [ 1913 Webster ]

a. [ Cf. F. heptagonal. ] Having seven angles or sides. [ 1913 Webster ]

Heptagonal numbers (Arith.), the numbers of the series 1, 7, 18, 34, 55, etc., being figurate numbers formed by adding successively the terms of the arithmetical series 1, 6, 11, 16, 21, etc. [ 1913 Webster ]

a. [ Cf. F. hexagonal. ] Having six sides and six angles; six-sided. [ 1913 Webster ]

Hexagonal system. (Crystal.) See under Crystallization. [ 1913 Webster ]

adv. In an hexagonal manner. [ 1913 Webster ]

n. [ Macro- + diagonal. ] (Crystallog.) The longer of two diagonals, as of a rhombic prism. See Crystallization. [ 1913 Webster ]

a. Having eight sides and eight angles. [ 1913 Webster ]

n. [ Ortho- + diagonal. ] (Crystallog.) The diagonal or lateral axis in a monoclinic crystal which is at right angles with the vertical axis. [ 1913 Webster ]

a. [ Cf. F. pentagonal, pentagone, L. pentagonus, pentagonius, Gr. &unr_;. ] Having five corners or angles. [ 1913 Webster ]

Pentagonal dodecahedron. See Dodecahedron, and Pyritohedron. [ 1913 Webster ]

adv. In the form of a pentagon; with five angles. Sir T. Browne. [ 1913 Webster ]

a. 1. (Geom.) Of or pertaining to a tetragon; having four angles or sides; thus, the square, the parallelogram, the rhombus, and the trapezium are tetragonal fingers. [ 1913 Webster ]

2. (Bot.) Having four prominent longitudinal angles. [ 1913 Webster ]

3. (Crystallog.) Designating, or belonging to, a certain system of crystallization; dimetric. See Tetragonal system, under Crystallization. [ 1913 Webster ]