Definition
The group of organs and tissues responsible for taking oxygen from the air into the body and removing carbon dioxide. It includes the nose, mouth, throat, windpipe (trachea), bronchial tubes, and lungs, along with the muscles that drive breathing such as the diaphragm.
Plain English
The body system that handles breathing — moving air in and out of the lungs so the blood can pick up oxygen and get rid of carbon dioxide.
Context Anchor
Seen in aeromedical discussions of hypoxia, especially when explaining how the body gets oxygen at altitude.
Derivation
From the Latin respirare, meaning 'to breathe again' (re- 'again' + spirare 'to breathe'). The system's job is exactly that — the continuous, repeated act of breathing.
Why Pilots Care
Proper function is essential to avoid hypoxia when oxygen availability decreases with altitude; failure here directly affects pilot performance and safety.
Grounding Statement
If the air reaching your lungs does not provide enough usable oxygen, your whole body—especially your brain—can start working poorly.
Intuition Check
Do not think of the respiratory system as only “the lungs.” The lungs are central, but the term includes the breathing passages and the overall process of moving oxygen into the blood and carbon dioxide out.
Example Sentence 1
At higher altitudes, the respiratory system has to work harder to deliver enough oxygen to the bloodstream.
Example Sentence 2
Supplemental oxygen helps the respiratory system maintain adequate blood saturation during high-altitude operations.