Infrapatellar bursitis occurs when one or both of the bursa sacs inside the knee become irritated and inflamed resulting in swelling and knee pain. A bursa is a sac of synovial fluid, rich in protein and collagen.
In biology, motility is the ability of organisms and fluid to move or get around. A microbiologist might test and compare the motility of various single-celled organisms. An easy way to remember that motility means the ability to move without help is the mot- at the root of the word. It's the same root that's found in motor, which is, of course, the engine that drives a car. If you've got good motility then your motor is working.
Noun. 1. mobility-the quality of moving freely. quality-an essential and distinguishing attribute of something or someone; the quality of mercy is not strained--Shakespeare. locomotion, motive power, motivity-the power or ability to move. motility-ability to move spontaneously and independently.