Final answer:
The hip joint is a convex ball-and-socket synovial joint allowing triaxial movement, including flexion/extension, abduction/adduction, medial/lateral rotation, and circumduction.
Step-by-step explanation:
The question pertains to the hip joint and its characteristics such as surface shapes, degrees of freedom (DOF), joint type, and motions. The hip joint is a ball-and-socket synovial joint, which is characterized by the convex surface of the femoral head articulating with the concave acetabulum of the pelvis. This joint type allows for multiple degrees of freedom, specifically triaxial movement (three degrees of freedom), which includes flexion/extension, abduction/adduction, and medial/lateral rotation. Additionally, the hip joint is capable of circumduction, a combination of these motions.