**Di*ag"o*nal** (?), a. [L. *diagonalis*, fr. Gr. from to angle; through + 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.

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.

© Webster 1913.

**Di*ag"o*nal** (?), 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.

**2.** Engin.

A member, in a framed structure, running obliquely across a panel.

**3.**

A diagonal cloth; a kind of cloth having diagonal stripes, ridges, or welts made in the weaving.

© Webster 1913.