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The term [trapezoid] is formed by the root term [-trapez-] which arises from the Latin [trapezius] and itself a derivative of the Greek [τραπέζι] meaning "a small table", referring to an irregular four-sided shape. It also has the suffix [-oid] meaning "similar to". The word then means "similar to a four-sided table".
The Trapezoid bone is one of the four bones that comprise the distal row of the carpus or carpal bones that form the wrist. This bone is also known as the "lesser multiangular bone" because of its many angles, surfaces and sharp edges. The Latin name for this bone is os multtangulus minus.
The following text is from Gray's anatomy with annotations in []: "The superior surface, quadrilateral, smooth, and slightly concave, articulates with the navicular [scaphoid bone]. The inferior surface articulates with the proximal end of the second metacarpal bone; it is convex from side to side, concave from before backward and subdivided by an elevated ridge into two unequal facets. The dorsal [posterior] and volar [anterior] surfaces are rough for the attachment of ligaments, the former being the larger of the two. The lateral surface,convex and smooth, articulates with the greater multangular [trapezium bone]. The medial surface is concave and smooth in front, for articulation with the capitate [bone]; rough behind, for the attachment of an interosseous ligament."
The accompanying image shows the anterior (volar) surface of the wrist.