soleus

so·le·us

noun \ˈsō-lē-əs\

plural so·lei \-lē-ˌī\ also soleuses

Definition of SOLEUS

: a broad flat muscle of the calf of the leg that lies deep to the gastrocnemius, arises from the back and upper part of the tibia and fibula and from a tendinous arch between them, inserts by a tendon that unites with that of the gastrocnemius to form the Achilles tendon, and acts to flex the foot

Illustration of SOLEUS