Definition of pyriformis in US English:

pyriformis

(also piriformis)

noun

Anatomy Zoology
  • A gluteal (buttock) muscle, which arises from the sacrum and the ischium or sacrotuberous ligament and inserts into the greater trochanter of the femur, serving in humans to rotate the thigh laterally.

Origin

Late 17th century. From post-classical Latin pyriformis pyriform.

Pronunciation

pyriformis

/ˌpɪrɪˈfɔːmɪs/