Parallelogram

2 definitions found

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

  Parallelogram \Par`al*lel"o*gram\, n. [Gr. ?; ? parallel + ? to
     write: cf. F. parall['e]logramme. See {Parallel}, and
     {-gram}.] (Geom.)
     A right-lined quadrilateral figure, whose opposite sides are
     parallel, and consequently equal; -- sometimes restricted in
     popular usage to a rectangle, or quadrilateral figure which


     is longer than it is broad, and with right angles.
     [1913 Webster]
  
     {Parallelogram of velocities}, {parallelogram of forces},
     {parallelogram of accelerations}, {parallelogram of momenta},
        etc. (Mech.), a parallelogram the diagonal of which
        represents the resultant of two velocities, forces,
        accelerations, momenta, etc., both in quantity and
        direction, when the velocities, forces, accelerations,
        momenta, etc., are represented in quantity and direction
        by the two adjacent sides of the parallelogram.
        [1913 Webster]

From WordNet (r) 2.0 [wn]:

  parallelogram
       n : a quadrilateral whose opposite sides are both parallel and
           equal in length [ant: {trapezium}]