"dead cert" meaning in English

{
  "etymology_templates": [
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      "args": {
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        "2": "dead certainty"
      },
      "expansion": "Clipping of dead certainty",
      "name": "clipping"
    }
  ],
  "etymology_text": "Clipping of dead certainty.",
  "forms": [
    {
      "form": "dead certs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "dead cert (plural dead certs)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "kind": "other",
          "name": "English entries with incorrect language header",
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          "source": "w"
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      "examples": [
        {
          "text": "It's a dead cert that United will beat City in the cup.",
          "type": "example"
        },
        {
          "ref": "1962, Dick Francis, chapter 4, in Dead Cert, published 2004, page 46",
          "text": "“Jockeys are bad tipsters. But that one was a cert, a dead cert.” A dead cert. The casual, everyday racing expression jabbed in my mind like a needle.",
          "type": "quotation"
        },
        {
          "ref": "2020 May 20, Paul Clifton, “A hydrogen solution to decarbonisation?”, in Rail, page 54",
          "text": "\"Tees Valley is our first target. It's not a dead cert yet, but we are very hopeful.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A practically guaranteed outcome."
      ],
      "id": "en-dead_cert-en-noun-N5NsA6Qg",
      "links": [
        [
          "guaranteed",
          "guaranteed"
        ],
        [
          "outcome",
          "outcome"
        ]
      ],
      "raw_glosses": [
        "(informal) A practically guaranteed outcome."
      ],
      "synonyms": [
        {
          "word": "sure thing"
        }
      ],
      "tags": [
        "informal"
      ]
    }
  ],
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      "tags": [
        "Southern-England"
      ],
      "text": "Audio (Southern England)"
    }
  ],
  "word": "dead cert"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "dead certainty"
      },
      "expansion": "Clipping of dead certainty",
      "name": "clipping"
    }
  ],
  "etymology_text": "Clipping of dead certainty.",
  "forms": [
    {
      "form": "dead certs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "dead cert (plural dead certs)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        "English clippings",
        "English countable nouns",
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        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with audio links",
        "English terms with quotations",
        "English terms with usage examples"
      ],
      "examples": [
        {
          "text": "It's a dead cert that United will beat City in the cup.",
          "type": "example"
        },
        {
          "ref": "1962, Dick Francis, chapter 4, in Dead Cert, published 2004, page 46",
          "text": "“Jockeys are bad tipsters. But that one was a cert, a dead cert.” A dead cert. The casual, everyday racing expression jabbed in my mind like a needle.",
          "type": "quotation"
        },
        {
          "ref": "2020 May 20, Paul Clifton, “A hydrogen solution to decarbonisation?”, in Rail, page 54",
          "text": "\"Tees Valley is our first target. It's not a dead cert yet, but we are very hopeful.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A practically guaranteed outcome."
      ],
      "links": [
        [
          "guaranteed",
          "guaranteed"
        ],
        [
          "outcome",
          "outcome"
        ]
      ],
      "raw_glosses": [
        "(informal) A practically guaranteed outcome."
      ],
      "tags": [
        "informal"
      ]
    }
  ],
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      "tags": [
        "Southern-England"
      ],
      "text": "Audio (Southern England)"
    }
  ],
  "synonyms": [
    {
      "word": "sure thing"
    }
  ],
  "word": "dead cert"
}