Sartorius is a long thin muscle that runs down the length of the thigh.
The name sartorius comes from the Latin word sartus meaning 'patched or repaired'. This refers the cross-legged position in which tailors once sat. The action of sartorius is to cross the legs, by flexion of the knee, and flexion and lateral rotation the hip. Sartorius does not have a very strong action.
Sartorius is also the surname of a family of Polish nobility also established in Spain.