noun
echinoderm
ih-KY-nuh-durm
Echinoderm (noun) means a radially symmetric, spiny-skinned marine animal of the phylum Echinodermata, such as a sea star, sea urchin, or sea cucumber. Example: “A sea urchin is an echinoderm.”
noun
1
technical A radially symmetric, spiny-skinned marine animal of the phylum Echinodermata, such as a sea star, sea urchin, or sea cucumber.
"A sea urchin is an echinoderm."
"The aquarium has a touch tank where visitors can handle echinoderms such as sea stars."
"Biologists classify sand dollars as echinoderms."
How to use echinoderm
Learner’s notesIn plain EnglishA spiny-skinned sea animal like a sea star or sea urchin.
When to use it
This is a scientific term used mainly in biology and marine science.
Memory tip
Echino- and -derm together point to the spiny skin that defines the group.
Trace the full origin ↓
Common pairings
marine echinoderm
echinoderm larvae
echinoderm skeleton
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A sea urchin is an _____.
Etymology
English took the word from French échinoderme, which was built from echino- and -derm. It follows the plural of the 18th-century Latin form echinoderma.
Frequently asked questions
What is an echinoderm?
An echinoderm is a spiny-skinned marine animal of the phylum Echinodermata. It has radial symmetry.
What animals are echinoderms?
Echinoderms include sea stars, sea urchins, sea cucumbers, crinoids, and sand dollars.
Are echinoderms invertebrates?
Yes. Echinoderms are a kind of invertebrate, meaning they have no backbone.
What is the meaning of echinoderm?
"echinoderm" (noun) means a radially symmetric, spiny-skinned marine animal of the phylum Echinodermata, such as a sea star, sea urchin, or sea cucumber.
