"insider baseball" meaning in English

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      "expansion": "insider baseball (uncountable)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "inside baseball"
        }
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      "glosses": [
        "Misconstruction of inside baseball"
      ],
      "id": "en-insider_baseball-en-noun-Dqk1J10Q",
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          "inside baseball",
          "inside baseball#English"
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      "tags": [
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    }
  ],
  "word": "insider baseball"
}

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      "expansion": "insider baseball (uncountable)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "inside baseball"
        }
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      "glosses": [
        "Misconstruction of inside baseball"
      ],
      "links": [
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      "tags": [
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  ],
  "word": "insider baseball"
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