According to www.wikipedia.com a herd of hippopotami is called a pod, herd, dale or bloat and that the plural of hippopotamus is variously: hippopatami, hippopotamus or simply hippopotamus.
Personally, I like the term bloat simply because it sounds funny. :)
As far as the plural of hippopotamus goes, I think hippopotami makes the most sense as it follows the pattern of cactus/cacti and octopus/octopi.
There are several names available, Pod, Herd, Dale or Bloat
A Hippopotamus
A baby hippopotamus is called a calf.
A group can either be called "hippopotami" or "hippopotamuses."
They are mammals, and they belong to a group called Cetartiodactyla. Their closest living relatives are dolphins and whales!
hippopotamus
hippopotamus
A hippopotamus is sometimes called a river horse.
hippopotamus
A male hippopotamus is called a bull
A young Hippopotamus is called a calf.
Hippopotamus comes from the greek word "hippo" meaning horse. The greeks called hippopotamus' water horses. Hope this answer was helpful
calf