starfish

American  

[stahr-fish] / ˈstɑrˌfɪʃ /

noun

starfishes plural

1. any echinoderm of the class Asteroidea, having the body radially arranged, usually in the form of a star, with five or more rays or arms radiating from a central disk; asteroid.

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starfish British  

/ ˈstɑːˌfɪʃ /

noun

1. any echinoderm of the class Asteroidea , such as Asterias rubens , typically having a flattened body covered with a flexible test and five arms radiating from a central disc

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starfish Scientific  

/ stär′fĭsh′ /

1. Any of various marine echinoderms of the class Asteroidea, having a star-shaped body usually with five arms. The arms have rows of little suckers on the undersides, called tube feet, with which the animal moves around and grasps prey. Many species extrude their stomach onto prey and digest it externally. Starfish can grow new arms if any are lost, and in one species, a whole individual can be regenerated from a single piece of arm. Starfish are related to sea urchins and sea cucumbers.

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Other Word Forms

Inflected Forms

noun

• starfishes
  plural
• starfish
  plural

Etymology

Origin of starfish

First recorded in 1530–40; star + fish

Explanation

A starfish is a marine animal with five pointed arms. Starfish live in all the oceans on Earth. Not all starfish are star-shaped (though most are), and they're not actually fish. These fascinating invertebrates, also called sea stars, live in every possible marine habitat, from the depths of the ocean to coral reefs and tide pools. Starfish are usually shaped like a five-pointed star, but they can have as many as 50 arms whose tiny suckers help them move along the ocean floor. They come in almost every color imaginable, including white, purple, bright red, and pink.

Example Sentences

Low tide at a rock pool means a peek at the starfish and sea slugs hidden among the stones.

From The Wall Street Journal • May 22, 2026

This can lead to "starballing" where starfish curl up to float with the current which can make them vulnerable to beach strandings.

From BBC • Sep. 9, 2025

Rough seas and strong winds are usually responsible for dislodging starfish from their seabed habit.

From BBC • Sep. 9, 2025

One example: In the Season 13 episode “Patrick the Mailman,” the starfish delivers a letter to SpongeBob and asks him, “Do you know where this Spon-gee-Boob Squir-pa-Nants lives?”

From Los Angeles Times • Jul. 3, 2025

Ruby plops herself on the floor and then spreads out on her back like a starfish.

From "Shouting at the Rain" by Lynda Mullaly Hunt