|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
conus arteriosus conus ar·te·ri·o·sus (är-tēr'ē-ō'səs)
A conical extension of the right ventricle in the heart, from which the pulmonary artery originates. Also called arterial cone, infundibulum.