1. Plural of postcava; the posterior vena cava, a major vein in vertebrates that returns blood from the lower body to the heart.
Usage: anatomy; technical; chiefly used in comparative anatomy and zoology

Examples

• The postcavae in fish differ structurally from those in mammals.
• Anatomists examined the postcavae to understand blood flow in the specimen.
• The postcavae merge with the hepatic veins before entering the heart.
• In comparative vertebrate anatomy, the postcavae are key structures for study.