parallelogram

/ˈpɛrəˌlɛləˈgræm/

/pɛrəˈlɛləgræm/

Other forms: parallelograms

A parallelogram is a four-sided object that has parallel opposite sides. A square is a parallelogram. If you take the square and tilt it to one side, it’s still a parallelogram as long as its lines remain parallel.

A parallelogram is a two-dimensional object that you might have already encountered in geometry class. You can recognize a parallelogram by its parallel opposite sides, and also by its opposite angles that are equal. Adjacent angles on a parallelogram always add up to 180 degrees. If the angles of a parallelogram are 90 degrees, then it’s straight up and down, like a square or a rectangle.

Definitions of parallelogram

1. noun

   a quadrilateral whose opposite sides are both parallel and equal in length
   antonyms:

   trapezium

   a quadrilateral with no parallel sides

   types:

   diamond, lozenge, rhomb, rhombus

   a parallelogram with four equal sides; an oblique-angled equilateral parallelogram

   rhomboid

   a parallelogram with adjacent sides of unequal lengths; an oblique-angled parallelogram with only the opposite sides equal

   rectangle

   a parallelogram with four right angles

   foursquare, square

   (geometry) a plane rectangle with four equal sides and four right angles; a four-sided regular polygon

   box

   a rectangular drawing

   type of:

   quadrangle, quadrilateral, tetragon

   a four-sided polygon