[1] : 708 The superior surface, quadrilateral, smooth, and slightly concave, articulates with the scaphoid.

The medial surface is concave and smooth in front, for articulation with the capitate; rough behind, for the attachment of an interosseous ligament.

The carpal bones function as a unit to provide a bony superstructure for the hand.

[2] The etymology derives from the Greek trapezion which means "irregular quadrilateral," from tra- "four" and peza "foot" or "edge."

This article incorporates text in the public domain from page 225 of the 20th edition of Gray's Anatomy (1918)