Superior radioulnar joint is:

The radius and the ulna are connected at their upper and lower extremities by synol joints, termed the superior and inferior radio-ulnar joints.The superior radio ulnar joint is a pivot-joint between the circumference of the head of the radius and the osseofibrous ring formed by the radial notch of the ulna and the annular ligament. The inferior radio ulnar joint is a pivot-joint formed between the head of the ulna and the ulnar notch of the lower end of the radius; Joints: A joint or place of aiculation is formed where 2 or more bones come inclose contact in the body and are attached to each other by ligaments or cailageClassification of joints: The aiculations are divided into three classes: synahroses or immovable, amphiahroses or slightly movable, and diahroses or freely movable. ClassesTypesExamplesFIBROUS JOINTS (SYNAHROSES) SUTURES SYNDESMOSES GOMPHOSESCranial sutures Inferior tibiofibular joint Bone and socket jointCAILAGINOUS JOINTS (AMPHIAHROSES) SYNCHONDROSES (Hyaline cailage) SYMPHYSES (Fibrocailage)Epiphyseal plates Pubic symphesisSYNOL JOINTS (DIAHROSES) UNIAXIALGINGLYMUS (Hinge)TROCHOID (Pivot) BIAXIALCONDYLOID or ELLIPSOID SADDLE TRIAXIALBALL AND SOCKETPLANARElbow and interphalangeal joints Superior and inferior radioulnar jointRadiocarpal (wrist) joints, and metacarpophalangeal jointsCarpometacarpal joint of thumb Shoulder and hip jointIntercarpal and intearsal jointsRef: The human body: an introduction to structure and function, By A. Faller, Michael Sch?unke, Gabriele Schunke, Page 122