1) Elephant 2) Mastodon 3) Mastodont 4) Proboscidian 1) Eutherian 2) Eutherian mammal 3) Having a proboscis 4) Placental 5) Placental mammal 6) Proboscidian 
• (a.) Proboscidian.
any of the group of mammals that includes elephants and their extinct relatives such as mammoths and mastodons. Although only three species of ...
Pro`bos·cid'e·an adjective (Zoology) Proboscidian. 
[n] - massive herbivorous mammals having tusks and a long trunk
proboscidian, proboscidean Of or belonging to the Proboscidea, an order of mammals typified by a trunk or proboscis and including the elephant.
proboscidian noun massive herbivorous mammals having tusks and a long trunk
pertaining to or resembling a proboscis. · having a proboscis. · belonging or pertaining to the mammals of the order Proboscidea, characterized by a flexible trunk formed of the nostrils and upper lip, large tusks, a massive body, and columnar legs, comprising the elephant and the now-extinct mammoth and mastodon.