The occult significance of Aquarius is knowledge. Aquarius, the sign of the water bearer, is an eminently revolutionary sign. There are four types of knowledge or secret science. We need to know what these four types of knowledge are.
Upper limb. The upper limb or upper extremity is the region in a vertebrate animal extending from the deltoid region to the hand, including the arm, axilla and shoulder.
U stands for Upper extremities - concerning the hands, arms, shoulder girdle, and upper spine (cervical, thoracic, and upper lumbar) in regard to strength, range of motion, and general efficiency. 1  No loss of digits or limitation of motion; no demonstrable abnormality; able to do hand to hand fighting.