Definition of sea urchin in English:

sea urchin

Line breaks: sea ur¦chin

noun

A marine echinoderm which has a spherical or flattened shell covered in mobile spines, with a mouth on the underside and calcareous jaws.
  • Class Echinoidea
More example sentences
  • The sea urchin is one of the few marine organisms whose genome has been sequenced.
  • The inner shell of a sea urchin is a hollow globe, scored in five curved sections that taper at the ends into a small hole at the top and bottom.
  • The red sea urchin's body is domed above and flat below.

Definition of sea urchin in:

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Word of the day glee
Pronunciation: glē
noun
great delight