What does "tendinitis" mean and where does it commonly occur?

Tendinitis means inflammation of a tendon, from tendin meaning tendon and itis meaning inflammation. Tendons are tough fibrous cords that connect muscles to bones. Tendinitis commonly occurs in the shoulder as rotator cuff tendinitis, in the elbow as lateral epicondylitis also called tennis elbow, in the wrist as de Quervain tendinitis, in the knee as patellar tendinitis, and in the ankle as Achilles tendinitis. It is usually caused by repetitive motions, overuse, or sudden increase in activity intensity.