| a small mass of cells and nerve endings adjacent to the carotid sinus that, in response to chemical changes in the blood, adjusts the respiratory rate. |

carotid body n.
A small epithelioid structure, located just above the bifurcation of the common carotid artery on each side that serves as a chemoreceptor organ responsive to lack of oxygen, excess of carbon dioxide, and increased concentration of hydrogen ions. Also called intercarotid body.
| carotid body
A mass of tissue near the carotid sinus that contains chemical receptors sensitive to oxygen and pH levels in the blood and that is involved in the regulation of respiratory activity. |