seahorse

American  

[see-hawrs] / ˈsiˌhɔrs /

Or sea horse

noun

seahorses plural

1. any fish of the genus Hippocampus, of the pipefish family, having a prehensile tail, an elongated snout, and a head bent at right angles to the body.

2. a fabled marine animal with the foreparts of a horse and the hind parts of a fish.

3. a walrus.

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Other Word Forms

Noun Inflected Forms

• seahorses
  plural

Etymology

Origin of seahorse

First recorded in 1425–75; late Middle English sehors, possibly meaning “walrus”; compare German Seeross; see origin at sea ( def. ), horse

Explanation

A seahorse is a tiny fish with a vaguely horse-shaped head. Seahorses swim upright, with their curled tails pointing down. Seahorses look different from most fish, with hard, bony exteriors and long snouts. They're also different from almost all other animals because male seahorses give birth to babies, after carrying eggs deposited by the female. The scientific genus of seahorses is Hippocampus, from the Ancient Greek words hippos, "horse," and kampos, "sea monster." There's also a section of the human brain called the hippocampus, named for its resemblance to the seahorse.

Example Sentences

See Examples For:

seahorse seahorses

Designed by Charles T. Meier and engineered by project manager Kyle Amerine, the massive seahorse nodded as it coached over a dozen fin-flapping baby sea creatures as they performed a synchronized swimming routine.

From Los Angeles Times ● Jan. 3, 2026

Talia Greis, from Australia, won Macro, with an abstract portrait of a potbelly seahorse in the murky waters near Bare Island, Sydney.

From BBC ● Feb. 19, 2024

The scientists were able to show that the structure of Mcf1 resembles a seahorse with a head containing several toxic payloads, while the tail region can attach to target cells.

From Science Daily ● Jan. 31, 2024

In 2020, these seahorses were named the second most endangered kind of seahorse in the world.

From NewsForKids.net ● Aug. 3, 2023

I look down at where my seahorse tattoo should be.

From "They Both Die at the End" by Adam Silvera

The other tanks, for Marcellus and the seahorses and the wolf eels, were on a stage.

From Los Angeles Times ● May 7, 2026

Thousands of birds and seahorses were killed as a result, ecologist Vladyslav Belinsky said.

From Barron's ● Feb. 27, 2026

But even this strange new world isn’t beyond the reach of Evie’s siblings, who follow their sister on seahorses.

From The Wall Street Journal ● Feb. 20, 2026

However, BBC News also found British companies selling dried seahorses, which can only be traded in the UK if the seller can certify they were sustainably harvested.

From BBC ● Dec. 11, 2025

“We will march into the sea and out again. Under the waves we will ride seahorses, and mermaids will blow seashells to announce our coming, oh, oh, oh.”

From "A Dance with Dragons" by George R. R. Martin