ˈsōlēəs noun
( plural so·lei -ēˌī ; also soleuses )
Etymology: New Latin, from Latin solea sole of the foot
: a broad flat muscle of the calf of the leg lying immediately below the gastrocnemius, arising from the back and upper part of the tibia and fibula and from a tendinous arch between them, and inserting by a tendon that unites with that of the gastrocnemius to form the Achilles' tendon