"simian shelf" meaning in English

{
  "forms": [
    {
      "form": "simian shelves",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "simian shelves"
      },
      "expansion": "simian shelf (plural simian shelves)",
      "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",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Anatomy",
          "orig": "en:Anatomy",
          "parents": [
            "Biology",
            "Medicine",
            "Sciences",
            "Healthcare",
            "All topics",
            "Health",
            "Fundamental",
            "Body"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A bony thickening on the front of the mandible of an ape."
      ],
      "id": "en-simian_shelf-en-noun-awHd6vkr",
      "links": [
        [
          "anatomy",
          "anatomy"
        ],
        [
          "bony",
          "bony"
        ],
        [
          "thickening",
          "thickening"
        ],
        [
          "mandible",
          "mandible"
        ],
        [
          "ape",
          "ape"
        ]
      ],
      "raw_glosses": [
        "(anatomy) A bony thickening on the front of the mandible of an ape."
      ],
      "topics": [
        "anatomy",
        "medicine",
        "sciences"
      ],
      "wikipedia": [
        "simian shelf"
      ]
    }
  ],
  "word": "simian shelf"
}

{
  "forms": [
    {
      "form": "simian shelves",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "simian shelves"
      },
      "expansion": "simian shelf (plural simian shelves)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Pages with 1 entry",
        "en:Anatomy"
      ],
      "glosses": [
        "A bony thickening on the front of the mandible of an ape."
      ],
      "links": [
        [
          "anatomy",
          "anatomy"
        ],
        [
          "bony",
          "bony"
        ],
        [
          "thickening",
          "thickening"
        ],
        [
          "mandible",
          "mandible"
        ],
        [
          "ape",
          "ape"
        ]
      ],
      "raw_glosses": [
        "(anatomy) A bony thickening on the front of the mandible of an ape."
      ],
      "topics": [
        "anatomy",
        "medicine",
        "sciences"
      ],
      "wikipedia": [
        "simian shelf"
      ]
    }
  ],
  "word": "simian shelf"
}