| CHN | carbon, hydrogen, and nitrogen; child neurology; Chinese [hamster]; community health network; commun... |
|---|---|
| C/N | carbon/nitrogen [ratio]; carrier/ noise [ratio] |
| CO | carbon monoxide; cardiac output; castor oil; casualty officer; centric occlusion; cervical orthosis;... |
| CO2 | carbon dioxide |
| ctCO2 | carbon dioxide concentration |