"card clash" meaning in English

{
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "card clash (uncountable)",
      "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": [
        {
          "ref": "2014 August 13, Gwyn Topham, “Open data and driverless buses: how London transport heads to the future”, in The Guardian",
          "text": "From September passengers will be able to enter by tapping their credit card at the barriers – with the new Tannoy announcement \"avoid card clash\" joining the familiar \"mind the gap\" as the sound of the Underground. Card clash can be avoided with an even newer technology, contactless payments via mobile phones: […]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "The situation where two or more contactless payment cards are simultaneously detected by a card reader, possibly resulting in the wrong card, or more than one card, being charged."
      ],
      "id": "en-card_clash-en-noun-Iqh5nyyc",
      "links": [
        [
          "contactless",
          "contactless"
        ],
        [
          "payment",
          "payment"
        ],
        [
          "card",
          "card"
        ],
        [
          "card reader",
          "card reader"
        ],
        [
          "charge",
          "charge"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "card clash"
}

{
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "card clash (uncountable)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations",
        "English uncountable nouns"
      ],
      "examples": [
        {
          "ref": "2014 August 13, Gwyn Topham, “Open data and driverless buses: how London transport heads to the future”, in The Guardian",
          "text": "From September passengers will be able to enter by tapping their credit card at the barriers – with the new Tannoy announcement \"avoid card clash\" joining the familiar \"mind the gap\" as the sound of the Underground. Card clash can be avoided with an even newer technology, contactless payments via mobile phones: […]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "The situation where two or more contactless payment cards are simultaneously detected by a card reader, possibly resulting in the wrong card, or more than one card, being charged."
      ],
      "links": [
        [
          "contactless",
          "contactless"
        ],
        [
          "payment",
          "payment"
        ],
        [
          "card",
          "card"
        ],
        [
          "card reader",
          "card reader"
        ],
        [
          "charge",
          "charge"
        ]
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "card clash"
}