Final answer:
The superficial anatomical name for just the posterior portion of the lower leg is the calf. It is formed by the gastrocnemius and the soleus muscles, which are responsible for lowering the sole of the foot to the ground and other movements.
Step-by-step explanation:
The superficial anatomical name for just the posterior portion of the lower leg is the calf. The calf is formed by the two muscles called the gastrocnemius and the soleus, which are located at the back of the lower leg. These muscles are responsible for lowering the sole of the foot to the ground, as well as assisting in movements like jumping or moving the back of the lower legs up and back toward the buttocks.