"anyone's guess" meaning in English

{
  "head_templates": [
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      "args": {
        "1": "?"
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      "expansion": "anyone's guess",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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          "parents": [
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          "kind": "other",
          "name": "English singularia tantum",
          "parents": [
            "Singularia tantum",
            "Nouns",
            "Lemmas"
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          "source": "w"
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      "examples": [
        {
          "ref": "2011 January 5, Jonathan Stevenson, “Arsenal 0 - 0 Man City”, in BBC",
          "text": "It was a disappointing way for the game to finish, with Sagna guilty of leaning his head in towards Zabaleta's after a challenge by the touchline, though what the Argentine did to warrant a dismissal is anyone's guess.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A mystery; something unpredictable."
      ],
      "id": "en-anyone's_guess-en-noun-iGm8OrP2",
      "links": [
        [
          "mystery",
          "mystery"
        ],
        [
          "unpredictable",
          "unpredictable"
        ]
      ],
      "raw_glosses": [
        "(idiomatic) A mystery; something unpredictable."
      ],
      "related": [
        {
          "word": "your guess is as good as mine"
        }
      ],
      "tags": [
        "idiomatic"
      ],
      "translations": [
        {
          "code": "fr",
          "lang": "French",
          "sense": "Translations",
          "word": "mystère"
        },
        {
          "code": "fr",
          "lang": "French",
          "sense": "Translations",
          "tags": [
            "feminine"
          ],
          "word": "surprise"
        },
        {
          "code": "el",
          "lang": "Greek",
          "roman": "entelós avévaio",
          "sense": "Translations",
          "tags": [
            "neuter"
          ],
          "word": "εντελώς αβέβαιο"
        },
        {
          "code": "ru",
          "lang": "Russian",
          "roman": "délo tjómnoje",
          "sense": "Translations",
          "word": "де́ло тёмное"
        }
      ]
    }
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      "audio": "en-au-anyone's guess.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/c/cf/En-au-anyone%27s_guess.ogg/En-au-anyone%27s_guess.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/c/cf/En-au-anyone%27s_guess.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "word": "anyone's guess"
}

{
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "anyone's guess",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "your guess is as good as mine"
    }
  ],
  "senses": [
    {
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        "English countable nouns",
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        "English idioms",
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        "English multiword terms",
        "English nouns",
        "English nouns with unknown or uncertain plurals",
        "English singularia tantum",
        "English terms with audio links",
        "English terms with non-redundant non-automated sortkeys",
        "English terms with quotations",
        "Translation table header lacks gloss"
      ],
      "examples": [
        {
          "ref": "2011 January 5, Jonathan Stevenson, “Arsenal 0 - 0 Man City”, in BBC",
          "text": "It was a disappointing way for the game to finish, with Sagna guilty of leaning his head in towards Zabaleta's after a challenge by the touchline, though what the Argentine did to warrant a dismissal is anyone's guess.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A mystery; something unpredictable."
      ],
      "links": [
        [
          "mystery",
          "mystery"
        ],
        [
          "unpredictable",
          "unpredictable"
        ]
      ],
      "raw_glosses": [
        "(idiomatic) A mystery; something unpredictable."
      ],
      "tags": [
        "idiomatic"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-au-anyone's guess.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/c/cf/En-au-anyone%27s_guess.ogg/En-au-anyone%27s_guess.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/c/cf/En-au-anyone%27s_guess.ogg",
      "tags": [
        "Australia"
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      "text": "Audio (AU)"
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  ],
  "translations": [
    {
      "code": "fr",
      "lang": "French",
      "sense": "Translations",
      "word": "mystère"
    },
    {
      "code": "fr",
      "lang": "French",
      "sense": "Translations",
      "tags": [
        "feminine"
      ],
      "word": "surprise"
    },
    {
      "code": "el",
      "lang": "Greek",
      "roman": "entelós avévaio",
      "sense": "Translations",
      "tags": [
        "neuter"
      ],
      "word": "εντελώς αβέβαιο"
    },
    {
      "code": "ru",
      "lang": "Russian",
      "roman": "délo tjómnoje",
      "sense": "Translations",
      "word": "де́ло тёмное"
    }
  ],
  "word": "anyone's guess"
}