Definition
A bladder is a sac-like organ in the body that stores urine before it is excreted. It is part of the urinary system, which filters waste from the blood. Think of it as a holding tank for liquid waste. Unlike the kidneys, which produce urine, the bladder simply stores it until you're ready to go to the bathroom. It expands as it fills and contracts when it empties. It's an essential organ for maintaining bodily functions.