"heart urchin" meaning in English

{
  "forms": [
    {
      "form": "heart urchins",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "heart urchin (plural heart urchins)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
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          "source": "w"
        },
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          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Sea urchins",
          "orig": "en:Sea urchins",
          "parents": [
            "Echinoderms",
            "Animals",
            "Lifeforms",
            "All topics",
            "Life",
            "Fundamental",
            "Nature"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1996, Marty Snyderman, chapter I, in Guide to Marine Life: Caribbean, Bahamas, Florida, page 129:",
          "text": "Red heart urchins, like other heart urchins, are usually buried under the sand and are only seen on rare occasions.",
          "type": "quote"
        },
        {
          "ref": "2003, Gunther J. Eble, “Developmental Morphospaces and Evolution”, in James P. Crutchfield, Peter Schuster, editors, Evolutionary Dynamics, page 47:",
          "text": "Spatangoids constitute a monophyletic group of heart urchins that appears in the early Cretaceous (145 M.Y. ago) and ranges to the Recent.",
          "type": "quote"
        },
        {
          "ref": "2007, Marian Armstrong, Wildlife and Plants, 3rd edition, volume 16, page 967:",
          "text": "The class of animals (Echinoidea) that sea urchins belong to includes sand dollars and heart urchins. Sand dollars are flat, while heart urchins are oval, covered in short spines with longer spines down their back.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Any echinoderm of the class Spatangoida."
      ],
      "id": "en-heart_urchin-en-noun-F1kaLBRx",
      "links": [
        [
          "echinoderm",
          "echinoderm"
        ],
        [
          "Spatangoida",
          "Spatangoida#Translingual"
        ]
      ],
      "related": [
        {
          "word": "sand dollar"
        },
        {
          "word": "sea urchin"
        }
      ],
      "synonyms": [
        {
          "sense": "any species of Spatangoida",
          "word": "spatangoid"
        }
      ],
      "wikipedia": [
        "heart urchin"
      ]
    }
  ],
  "word": "heart urchin"
}

{
  "forms": [
    {
      "form": "heart urchins",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "heart urchin (plural heart urchins)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "sand dollar"
    },
    {
      "word": "sea urchin"
    }
  ],
  "senses": [
    {
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        "Pages with 1 entry",
        "Pages with entries",
        "Quotation templates to be cleaned",
        "en:Sea urchins"
      ],
      "examples": [
        {
          "ref": "1996, Marty Snyderman, chapter I, in Guide to Marine Life: Caribbean, Bahamas, Florida, page 129:",
          "text": "Red heart urchins, like other heart urchins, are usually buried under the sand and are only seen on rare occasions.",
          "type": "quote"
        },
        {
          "ref": "2003, Gunther J. Eble, “Developmental Morphospaces and Evolution”, in James P. Crutchfield, Peter Schuster, editors, Evolutionary Dynamics, page 47:",
          "text": "Spatangoids constitute a monophyletic group of heart urchins that appears in the early Cretaceous (145 M.Y. ago) and ranges to the Recent.",
          "type": "quote"
        },
        {
          "ref": "2007, Marian Armstrong, Wildlife and Plants, 3rd edition, volume 16, page 967:",
          "text": "The class of animals (Echinoidea) that sea urchins belong to includes sand dollars and heart urchins. Sand dollars are flat, while heart urchins are oval, covered in short spines with longer spines down their back.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Any echinoderm of the class Spatangoida."
      ],
      "links": [
        [
          "echinoderm",
          "echinoderm"
        ],
        [
          "Spatangoida",
          "Spatangoida#Translingual"
        ]
      ],
      "wikipedia": [
        "heart urchin"
      ]
    }
  ],
  "synonyms": [
    {
      "sense": "any species of Spatangoida",
      "word": "spatangoid"
    }
  ],
  "word": "heart urchin"
}