An Etymological Dictionary of Astronomy and Astrophysics

A → quadrilateral all of whose angles are → right angles.

Etymology (EN): M.Fr. rectangle, from M.L. rectangulum “a triangle having a right angle,” from rect-, combining form of rectus→ right + angulum, → angle.

Etymology (PE): Râstgušé, from râst, → right, + gušé “corner, angle;” Mid.Pers. gôšak “corner.”