"ground rule" meaning in English

{
  "forms": [
    {
      "form": "ground rules",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "ground rule (plural ground rules)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Sports",
          "orig": "en:Sports",
          "parents": [
            "Human activity",
            "Human behaviour",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "_dis": "84 16",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A rule regarding play on a specific field, course, or court."
      ],
      "id": "en-ground_rule-en-noun-crNjuGas",
      "links": [
        [
          "sports",
          "sports"
        ]
      ],
      "raw_glosses": [
        "(sports) A rule regarding play on a specific field, course, or court."
      ],
      "topics": [
        "hobbies",
        "lifestyle",
        "sports"
      ]
    },
    {
      "categories": [],
      "examples": [
        {
          "ref": "2012, Andrew Martin, Underground Overground: A passenger's history of the Tube, Profile Books, page 109",
          "text": "The apparent success of the City and South London triggered an avalanche of bills for Tube railways, and in 1892 a Joint Select Committee of Parliament set out some ground rules.",
          "type": "quotation"
        },
        {
          "text": "Make sure everybody knows the ground rules for the trip before they leave."
        }
      ],
      "glosses": [
        "The basic rules or standards; whatever someone must know before proceeding."
      ],
      "id": "en-ground_rule-en-noun-anMVKlJs",
      "links": [
        [
          "rules",
          "rules"
        ],
        [
          "standards",
          "standards"
        ]
      ],
      "raw_glosses": [
        "(idiomatic, usually in the plural) The basic rules or standards; whatever someone must know before proceeding."
      ],
      "tags": [
        "idiomatic",
        "plural-normally"
      ],
      "translations": [
        {
          "_dis1": "1 99",
          "code": "fi",
          "lang": "Finnish",
          "sense": "the basic rules or standards; whatever someone must know before proceeding",
          "word": "perussääntö"
        },
        {
          "_dis1": "1 99",
          "code": "hu",
          "lang": "Hungarian",
          "sense": "the basic rules or standards; whatever someone must know before proceeding",
          "word": "alapszabály"
        }
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-au-ground rule.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/11/En-au-ground_rule.ogg/En-au-ground_rule.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/1/11/En-au-ground_rule.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "word": "ground rule"
}

{
  "categories": [
    "English countable nouns",
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English nouns",
    "English terms with audio links"
  ],
  "forms": [
    {
      "form": "ground rules",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "ground rule (plural ground rules)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "en:Sports"
      ],
      "glosses": [
        "A rule regarding play on a specific field, course, or court."
      ],
      "links": [
        [
          "sports",
          "sports"
        ]
      ],
      "raw_glosses": [
        "(sports) A rule regarding play on a specific field, course, or court."
      ],
      "topics": [
        "hobbies",
        "lifestyle",
        "sports"
      ]
    },
    {
      "categories": [
        "English idioms",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "2012, Andrew Martin, Underground Overground: A passenger's history of the Tube, Profile Books, page 109",
          "text": "The apparent success of the City and South London triggered an avalanche of bills for Tube railways, and in 1892 a Joint Select Committee of Parliament set out some ground rules.",
          "type": "quotation"
        },
        {
          "text": "Make sure everybody knows the ground rules for the trip before they leave."
        }
      ],
      "glosses": [
        "The basic rules or standards; whatever someone must know before proceeding."
      ],
      "links": [
        [
          "rules",
          "rules"
        ],
        [
          "standards",
          "standards"
        ]
      ],
      "raw_glosses": [
        "(idiomatic, usually in the plural) The basic rules or standards; whatever someone must know before proceeding."
      ],
      "tags": [
        "idiomatic",
        "plural-normally"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-au-ground rule.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/11/En-au-ground_rule.ogg/En-au-ground_rule.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/1/11/En-au-ground_rule.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "translations": [
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "the basic rules or standards; whatever someone must know before proceeding",
      "word": "perussääntö"
    },
    {
      "code": "hu",
      "lang": "Hungarian",
      "sense": "the basic rules or standards; whatever someone must know before proceeding",
      "word": "alapszabály"
    }
  ],
  "word": "ground rule"
}