When the break is lateral to the attachment of the trapezoid ligament, the fracture is usually transverse, and is almost always due to a fall on the back of the shoulder-the angle between the spine and the acromion process striking the ground.
"Manual of Surgery Volume Second: Extremities--Head--Neck. Sixth Edition."
Alexander Miles Alexis Thomson
As there is no common name for this figure, name it trapezoid at once.
"Guide to the Kindergarten and Intermediate Class and Moral Culture of Infancy."
Elizabeth P. Peabody Mary Mann
Pupils know from their work in arithmetic how to find the area of a triangle or a trapezoid, so that the area of the field is easily found.
"The Teaching of Geometry"
David Eugene Smith