The gracilis (also gracilis muscle, latin: musculus gracilis) is a long, slim, superficial muscle of the medial region of the thigh. The latin word gracilis means "slender".
The gracilis originates from the inferior pubic ramus medial to the origin site of the adductor magnus.
The fibers of the gracilis pass vertically downwards. The tendon of the gracilis together with the sartorius and semitendinosus form a common plate called the pes anserinus that inserts onto the tibial tuberosity.
The functions of the gracilis are adduction, flexion and internal rotation of the thigh at the hip joint, as well as flexion and internal rotation of the knee.
The gracilis is innervated by the anterior branch of the obturator nerve that arises from the lumbar plexus.