hippopotamus
Americannoun
noun
-
a very large massive gregarious artiodactyl mammal, Hippopotamus amphibius, living in or around the rivers of tropical Africa: family Hippopotamidae. It has short legs and a thick skin sparsely covered with hair
-
a related but smaller animal, Choeropsis liberiensis
Usage
Plural word for hippopotamus The plural form of hippopotamus can be either hippopotamuses or hippopotami. Hippopotamuses is more widely used. The plurals of several other singular words ending in -us are also formed this way, such as virus/viruses, sinus/sinuses, and walrus/walruses. Irregular plurals that are formed like hippopotami, such as cactus/cacti and fungus/fungi, derive directly from their original pluralization in Latin. However, the standard English plural -es ending is often also acceptable for these terms, as in cactuses.
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of hippopotamus
1555–65; < Latin < Greek hippopótamos, earlier híppos potámios literally, riverine horse (term used by Herodotus in his account of the Egyptian hippopotamus); compare Middle English ypotame, ypotamos, ypotanus < Old French ypotame < Medieval Latin ypotamus
Explanation
A hippopotamus is a huge African mammal that spends time in the water and on land. These herbivores are so enormous that one hippopotamus can eat two pounds of grass in a single feeding. Although they're plant-eaters, hippopotamuses are powerfully strong and fiercely protective. Experts consider them to be unpredictable as well, and if you happen to be in sub-saharan Africa, it's smart to keep your distance! Hippopotamus is from the Greek ho hippos potamios, "the horse of the river," and its roots, hippos, "horse," and potamos, "rushing water."
Vocabulary lists containing hippopotamus
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Aesthetes had been howling about the Freedom 250 set, a soaring, 92-foot tall structure which resembled one of those arcade machine claws in which you try and fail to grab a stuffed hippopotamus.
From The Wall Street Journal ● Jun. 15, 2026
Researchers examined numerous hippopotamus fossils using both genetic and radiocarbon dating methods.
From Science Daily ● Oct. 26, 2025
An "incredibly rare" female baby hippopotamus has been born at Edinburgh Zoo.
From BBC ● Nov. 5, 2024
Water Lily, a 45-year-old female hippopotamus who has lived at the Woodland Park Zoo since 1979, will be euthanized next week.
From Seattle Times ● Apr. 26, 2024
Noah was right; he looks exactly like a hippopotamus.
From "I'll Give You the Sun" by Jandy Nelson
Their list mainly included fish, but also mammals like beavers, river dolphins and hippopotami, as well as coldblooded creatures like crocodiles, giant salamanders and alligator snapping turtles.
From New York Times ● Jan. 21, 2020
Sometimes he dances, rather in the manner of the tutu-clad hippopotami in Walt Disney’s “Fantasia.”
From New York Times ● Mar. 18, 2016
The woman turned out to be Rebecca Francis, winner of the 2010 reality show Extreme Huntress, whose website features a gallery of the animals she’s hunted – from hippopotami in Mozambique to moose in Alaska.
From The Guardian ● Jul. 29, 2015
Photograph: John Bracegirdle/Alamy When the foundations of Trafalgar Square were dug in the 1830s, builders exposed river gravels crammed with the bones of hippopotami, straight-tusked elephants, giant deer, giant aurochs and lions.
From The Guardian ● May 24, 2013
In the second book we continued our hunting, and met leopards, elephants, hippopotami, wild boars, great serpents, etc., etc.
From Lost in the Jungle Narrated for Young People by Du Chaillu, Paul B. (Paul Belloni)
They confront many obstacles and dangers on their trek, including rivers that hide dangerous hippopotamuses and crocodiles, not to mention numerous predators they face on land.
From Textbooks ● Apr. 19, 2023
Mexican zoo authorities have agreed to help facilitate the transfer of the hippopotamuses, which have yet to be captured.
From Washington Times ● Mar. 2, 2023
The fossils date from early in the Eocene epoch, when Earth was home to ancient relatives of many modern mammals, including tapirs, hippopotamuses and humans.
From Scientific American ● Jan. 25, 2023
A mural depicts the entry to his infamous rural getaway, Hacienda Napoles, which featured, among other attractions, a zoo from which imported hippopotamuses have since escaped into the nearby countryside, causing environmental havoc.
From Los Angeles Times ● Oct. 10, 2022
I mean wild, like tigers and bears and hippopotamuses.
From "The World According to Humphrey" by Betty G. Birney
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
