Truncus may refer to:
Anatomy Persistent truncus arteriosus, a rare congenital heart disease Truncus arteriosus (embryology), part of an embryo's developing circulatory system A pulmonary artery (truncus pulmonalis) Lumbosacral trunk (truncus lumbosacralis) Costocervical trunk (truncus costocervicalis) Sympathetic trunk (truncus Sympaticus) Celiac artery (truncus coeliacus) Brachiocephalic artery (truncus brachiocephalicus) Trunk (anatomy) (truncus)
Other Truncus (mathematics), a particular algebraic curve