Pyramidalis

[Sommer]

a small, triangular muscle in the front of the abdomen

[Michiko]

More fully pyramidalis muscle. Any of several muscles that are more or less triangular in shape; (Anatomy) a muscle of the lower abdominal wall which arises from the pubic bone and inserts into and exerts tension on the linea alba, and (more fully pyramidalis nasi) the procerus muscle (now rare).