"backcard" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "back",
        "3": "card"
      },
      "expansion": "back + card",
      "name": "compound"
    }
  ],
  "etymology_text": "back + card",
  "forms": [
    {
      "form": "backcards",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "backcard (plural backcards)",
      "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"
        }
      ],
      "examples": [
        {
          "text": "Some collectors are interested in the backcards as well as the toys themselves.",
          "type": "example"
        }
      ],
      "glosses": [
        "The piece of card used as backing for the clear plastic bubble that contains a packaged toy."
      ],
      "id": "en-backcard-en-noun-eVreziv3",
      "links": [
        [
          "card",
          "card"
        ],
        [
          "backing",
          "backing"
        ],
        [
          "plastic",
          "plastic"
        ],
        [
          "package",
          "package"
        ],
        [
          "toy",
          "toy"
        ]
      ]
    }
  ],
  "word": "backcard"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "back",
        "3": "card"
      },
      "expansion": "back + card",
      "name": "compound"
    }
  ],
  "etymology_text": "back + card",
  "forms": [
    {
      "form": "backcards",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "backcard (plural backcards)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English compound terms",
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English nouns",
        "English terms with usage examples"
      ],
      "examples": [
        {
          "text": "Some collectors are interested in the backcards as well as the toys themselves.",
          "type": "example"
        }
      ],
      "glosses": [
        "The piece of card used as backing for the clear plastic bubble that contains a packaged toy."
      ],
      "links": [
        [
          "card",
          "card"
        ],
        [
          "backing",
          "backing"
        ],
        [
          "plastic",
          "plastic"
        ],
        [
          "package",
          "package"
        ],
        [
          "toy",
          "toy"
        ]
      ]
    }
  ],
  "word": "backcard"
}