Final answer:
The anatomical name for the kneecap is the patella, which helps in knee extension by protecting the tendon and increasing the quadriceps muscle's leverage.
Step-by-step explanation:
The anatomical name for the bone commonly known as the kneecap is patella. The patella is a small, triangular bone located in front of the knee joint. It is embedded in the tendon of the quadriceps femoris muscle and articulates with the patellar surface of the femur. This setup allows the patella to protect the tendon from rubbing against the femur and also increase the leverage of the quadriceps muscle during knee extension, effectively improving the extension of the knee joint.