cremaster muscle cre·mas·ter muscle (krə-mās'tər, krē-)
n.
A muscle with origin from the internal oblique and inguinal ligament, with insertion into the cremasteric fascia and pubic tubercle, with nerve supply from the genitofemoral nerve, and whose action raises the testicle. In the male, the muscle envelops the spermatic cord and the testis; in the female, it envelops the round ligament of the uterus.