[1] : The Collaborative International Dictionary of English v.0.48

perpendicular \per`pendic"ular\, n.
   1. a line at right angles to the plane of the horizon; a
      vertical line or direction.
      1913 webster

   2. geom. a line or plane falling at right angles on another
      line or surface, or making equal angles with it on each
      side.
      1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

perpendicular \per`pendic"ular\, a. l. perpendicularis,
   perpendicularius: cf. f. perpendiculaire. see perpendicle,
   pension.
   1. 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

   2. geom. 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.
      1913 webster
see also:
perpendicle pension perpendicular style 

[3] : WordNet (r) 2.0

perpendicular
     adj 1: intersecting at or forming right angles; "the axes are
            perpendicular to each other" ant: oblique, parallel
     2: at right angles to the plane of the horizon or a base line;
        "a vertical camera angle"; "the monument consists of two
        vertical pillars supporting a horizontal slab"; "measure
        the perpendicular height" syn: vertical ant: inclined,
         horizontal
     3: extremely steep; "the great perpendicular face of the cliff"
     n 1: a straight line at right angles to another line
     2: a gothic style in 14th and 15th century england;
        characterized by vertical lines and a four-centered
        tudor arch and fan vaulting syn: perpendicular style,
         english-gothic, english-gothic architecture
     3: a cord from which a metal weight is suspended pointing
        directly to the earth's center of gravity; used to
        determine the vertical from a given point syn: plumb
        line
     4: an extremely steep face
see also:
oblique parallel vertical inclined horizontal perpendicular style 
english-gothic english-gothic architecture plumb line 

[4] : Moby Thesaurus II by Grady Ward, 1.0

49 moby thesaurus words for "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

Perpendicular >> P Words
Perpendicular, definition of term: Perpendicular
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