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sea urchin

noun

Simple Definition of sea urchin

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of sea urchin

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

1591

First Known Use of sea urchin

1591


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




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