Hippopotamus comes from two Greek words that mean "horse" and "of the river". So the word means river horse. But a hippo is not a horse.
First, how do you say it?
hip-uh-POT-uh-mus
Five parts, and the loud one is the third: POT. You can also say hippo, which is shorter.
The weird part
A hippo does not look like a horse and does not live like a horse. It spends a lot of its day in the water, and its body is round and heavy.
So why does its name say horse?
The Greek parts
The word has two pieces:
- hippos: horse
- potamios: of the river, from potamos, which means river
Put together, they make hippos potamios, "the horse of the river". The ancient Greeks used that name for the animal. Late Latin kept it as hippopotamus, and English took the word from Latin.
An old English translation from 1601 simply wrote river-horse.
Before "hippopotamus"
English did not always use this long word. Around 1300, people used a shorter form, ypotame, which came through Old French. Later, English went back to the Greek-style word. A dictionary notes that the way the Greek word was built is a little unusual.
The long word appears in English in the 1500s. The short form hippo is much younger. It first appears in 1872.
The reveal
A hippo is not a horse. The ancient Greeks gave it that name, and the name stayed.
The word is a nickname that got stuck. It tells us what an old name was, not what the animal is.
🗣️ Natural Examples
The hippo opened its huge mouth at the zoo.
A baby hippopotamus is called a calf.
Hippos spend much of the day in the water.
The word hippopotamus is long, so people say hippo.
⚠️ Common Mistakes
Plural. Both forms are correct.
✅ two hippopotamuses
✅ two hippopotami
Spelling. Count the double P near the start, and the single P after it.
❌ hipopotamus, hippopotomus
✅ hippopotamus
Stress the middle.
❌ HIP-uh-pot-uh-mus
✅ hip-uh-POT-uh-mus
💬 In a Conversation
Leo: Is a hippo a kind of horse?
Mia: No.
Leo: But its name means river horse.
Mia: Names can be wrong. The hippo does not mind.
⏳ The OddLingo Timeline
Greek "hippos potamios" → Late Latin "hippopotamus" → Middle English "ypotame" (about 1300) → English "hippopotamus" (1500s) → "hippo" (1872)
🥡 The OddLingo Takeaway
The word says river horse, but the animal is not a horse.
A good spelling trick: the middle has a pot in it, so think of a hippo sitting in a pot.
For other words with misleading names, read Pineapple: No Pine, No Apple and Kangaroo.