perpendicular

• POS: Adjective, Noun
• HYPHEN: per=pen=dic=u=lar

CIDE DICTIONARY

perpendicular, a. [L. perpendicularis, perpendicularius: cf. F. perpendiculaire. See Perpendicle, Pension.].

•  Exactly upright or vertical; pointing to the zenith; at right angles to the plane of the horizon; extending in a right line from any point toward the center of the earth.  [1913 Webster]
•  At right angles to a given line or surface; as, the line ad is perpendicular to the line bc.  [1913 Webster]

Perpendicular style (Arch.), a name given to the latest variety of English Gothic architecture, which prevailed from the close of the 14th century to the early part of the 16th; -- probably so called from the vertical style of its window mullions.

perpendicular, n. 

•  A line at right angles to the plane of the horizon; a vertical line or direction.  [1913 Webster]
•  A line or plane falling at right angles on another line or surface, or making equal angles with it on each side.  [1913 Webster]

OXFORD DICTIONARY

perpendicular, adj. & n.
--adj.
1 a at right angles to the plane of the horizon. b (usu. foll. by to) Geom. at right angles (to a given line, plane, or surface).
2 upright, vertical.
3 (of a slope etc.) very steep.
4 (Perpendicular) Archit. of the third stage of English Gothic (15th-16th c.) with vertical tracery in large windows.
5 joc. in a standing position.
--n.
1 a perpendicular line.
2 a plumb-rule or a similar instrument.
3 (prec. by the) a perpendicular line or direction (is out of the perpendicular).

Derivative

perpendicularity n. perpendicularly adv.

Etymology

ME f. L perpendicularis f. perpendiculum plumb-line f. PER- + pendere hang

THESAURUS

perpendicular

air line, axis, azimuth circle, beeline, chord, diagonal, diameter, direct line, directrix, edge, erect, great-circle course, normal, orthodiagonal, orthogonal, orthometric, plumb, plunging, precipitous, radius, radius vector, rectangular, right angle, right line, right-angle, right-angled, right-angular, secant, segment, sheer, shortcut, side, stand-up, steep, straight, straight course, straight line, straight stretch, straight-up, straight-up-and-down, straightaway, streamline, tangent, transversal, up-and-down, upright, vector, vertical, vertical circle

ROGET THESAURUS

perpendicular

Verticality

N verticality, erectness, perpendicularity, right angle, normal, azimuth circle, wall, precipice, cliff, elevation, erection, square, plumb line, plummet, vertical, upright, erect, perpendicular, plumb, normal, straight, bolt, upright, rampant, standing up, rectangular, orthogonal, vertically, up, on end, up on end, right on end, a plomb, endwise, one one's legs, at right angles.

Perpendicularity

N perpendicularity, orthogonality, verticality, orthogonal, perpendicular, rectangular, uncorrelated.