Muscle pain is also known as myalgia, or simply aches in the muscles. Muscle aches are extremely common. Almost everybody has likely experienced discomfort in his or her muscles at some point.
MUSCLE
Definition:
Muscle is a body tissue consisting of long cells that contract when stimulated and produce motion, an organ that is essentially a mass of muscle tissue attached at either end to a fixed point and that by contracting moves or checks the movement of a body part.