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sea urchin

noun

Definition of sea urchin

  1. :  any of numerous echinoderms (class Echinoidea) that are usually enclosed in thin brittle globular tests covered with movable spines

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1591

First Known Use of sea urchin

1591

SEA URCHIN Defined for English Language Learners

sea urchin

noun

Definition of sea urchin for English Language Learners

  • : a small sea animal that lives on the ocean floor and is covered in sharp spines

SEA URCHIN Defined for Kids

sea urchin

noun

Definition of sea urchin for Students

  1. :  a small sea animal that is related to the starfish, lives on the sea bottom, and is enclosed in a roundish shell covered with spines that can move

Learn More about sea urchin

  1. Spanish Central: Translation of sea urchin Nglish: Translation of sea urchin for Spanish speakers Britannica.com: Encyclopedia article about sea urchin

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