Vena cava and Venous blood vessel

Vena cava noun - Either of two large veins that return oxygen-depleted blood to the right atrium of the heart.

Venous blood vessel and vena cava are semantically related. In some cases you can use "Venous blood vessel" instead a noun phrase "Vena cava".

Venous blood vessel noun - A blood vessel that carries blood from the capillaries toward the heart.

Vena cava and venous blood vessel are semantically related. Sometimes you can replace phrase "Vena cava" with "Venous blood vessel", this phrases are similar.