noun
atrium
An upper chamber of the heart that receives blood.
The diagram shows blood entering the heart's right atrium.
Etymology
Latin atrium named the main hall of a house. A heart atrium serves as a receiving chamber, collecting blood before it passes onward into a ventricle.
More examples
- Each atrium passes blood to a lower chamber.
- The two atria receive blood returning to the heart.
- Students traced the flow from the left atrium into the ventricle.
Forms
atrium · atria · atriums