CONUS ARTERIOSUS

noun (plural coni arteriosi) Etymology: New Latin, literally, arterial cone Date: circa 1860 a conical prolongation of the right ventricle in mammals from which the pulmonary arteries emerge, a prolongation of the ventricle of amphibians and some fishes that has a spiral valve separating venous blood going to the respiratory arteries from blood going to the aorta and systemic arteries