From Academic Kids
The term "hip" has several different meanings.
In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. The hip joint is the joint between the femur and the acetabulum of the pelvis.
- See also: hip replacement.
Hip, or hep, is also United States slang, an adjective meaning "fashionably current." African Americans introduced this use of the word into the English language lexicon, which is surmised to have its origin in the Wolof "hepi" or "hipi," which means "to open one's eyes" or otherwise be aware of what is going on.