"file shell" meaning in English

{
  "forms": [
    {
      "form": "file shells",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "file shell (plural file shells)",
      "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": "lifeform",
          "langcode": "en",
          "name": "Bivalves",
          "orig": "en:Bivalves",
          "parents": [
            "Mollusks",
            "Animals",
            "Lifeforms",
            "All topics",
            "Life",
            "Fundamental",
            "Nature"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Any mollusc of the genus Limatula."
      ],
      "id": "en-file_shell-en-noun-71MAdsoy",
      "links": [
        [
          "mollusc",
          "mollusc"
        ]
      ],
      "synonyms": [
        {
          "word": "file clam"
        }
      ],
      "wikipedia": [
        "file shell"
      ]
    }
  ],
  "word": "file shell"
}

{
  "forms": [
    {
      "form": "file shells",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "file shell (plural file shells)",
      "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",
        "Entries using missing taxonomic name (genus)",
        "en:Bivalves"
      ],
      "glosses": [
        "Any mollusc of the genus Limatula."
      ],
      "links": [
        [
          "mollusc",
          "mollusc"
        ]
      ],
      "synonyms": [
        {
          "word": "file clam"
        }
      ],
      "wikipedia": [
        "file shell"
      ]
    }
  ],
  "word": "file shell"
}