What is the anatomy term for azygos ?

azygos. [az´ĭ-gos] any unpaired part, as the azygos vein. azygous. azygos vein a vein beginning in the abdomen as a continuation of the ascending lumbar vein; it and its tributaries serve as vessels for the return of blood from the thorax to the superior vena cava.

its bassicly asking u   to answer it in your own words does that