"a cold day in Hell" meaning in All languages combined

{
  "categories": [
    {
      "kind": "other",
      "name": "Compositions en anglais",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Expressions en anglais",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Locutions nominales en anglais",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Anglais",
      "orig": "anglais",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_texts": [
    "Composé de a, cold (« froid »), day (« jour »), in et Hell (« enfer »), littéralement « un jour froid en enfer »."
  ],
  "lang": "Anglais",
  "lang_code": "en",
  "pos": "noun",
  "pos_title": "Locution nominale",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Métaphores en anglais",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Wiktionnaire:Exemples manquants en anglais",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Semaine aux quatre jeudis."
      ],
      "id": "fr-a_cold_day_in_Hell-en-noun-JFqVumF~",
      "tags": [
        "figuratively",
        "idiomatic"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\ə kəʊld dəɪ in hɛl\\"
    }
  ],
  "synonyms": [
    {
      "word": "when Hell freezes over"
    },
    {
      "word": "when pigs fly"
    }
  ],
  "word": "a cold day in Hell"
}

{
  "categories": [
    "Compositions en anglais",
    "Expressions en anglais",
    "Locutions nominales en anglais",
    "anglais"
  ],
  "etymology_texts": [
    "Composé de a, cold (« froid »), day (« jour »), in et Hell (« enfer »), littéralement « un jour froid en enfer »."
  ],
  "lang": "Anglais",
  "lang_code": "en",
  "pos": "noun",
  "pos_title": "Locution nominale",
  "senses": [
    {
      "categories": [
        "Métaphores en anglais",
        "Wiktionnaire:Exemples manquants en anglais"
      ],
      "glosses": [
        "Semaine aux quatre jeudis."
      ],
      "tags": [
        "figuratively",
        "idiomatic"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\ə kəʊld dəɪ in hɛl\\"
    }
  ],
  "synonyms": [
    {
      "word": "when Hell freezes over"
    },
    {
      "word": "when pigs fly"
    }
  ],
  "word": "a cold day in Hell"
}