organ
A body part that does a special job, like the heart.
An organ in your body is a part made of different tissues working together to do a specific job. Your heart is an organ that pumps blood. Your lungs are organs that help you breathe. Your brain is an organ that controls everything you do and think. Each organ has its own vital role, and most of them work constantly without you having to think about it.
Scientists group related organs into organ systems. Your digestive system includes organs like your stomach and intestines, which work together to break down food. Your circulatory system includes your heart and blood vessels, moving oxygen and nutrients throughout your body.
An organ is also a musical instrument with keyboards and pipes that creates sound when air flows through them. Church organs can be enormous, with hundreds of pipes creating everything from whisper-quiet notes to sounds that shake the building. Modern electronic organs use speakers instead of pipes but still capture that rich, layered sound. Playing the organ takes skill because organists often use both hands on different keyboards and their feet on pedals, all at the same time.