"brokered convention" meaning in English

{
  "forms": [
    {
      "form": "brokered conventions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "brokered convention (plural brokered conventions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "langcode": "en",
          "name": "US politics",
          "orig": "en:US politics",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "A political convention held during a presidential election when a political party fails to choose a nominee on the first round of delegate voting at the party's nominating convention."
      ],
      "id": "en-brokered_convention-en-noun-Y8IOhFhX",
      "raw_glosses": [
        "(US politics) A political convention held during a presidential election when a political party fails to choose a nominee on the first round of delegate voting at the party's nominating convention."
      ],
      "synonyms": [
        {
          "word": "open convention"
        }
      ],
      "tags": [
        "US"
      ],
      "topics": [
        "government",
        "politics"
      ]
    }
  ],
  "word": "brokered convention"
}

{
  "forms": [
    {
      "form": "brokered conventions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "brokered convention (plural brokered conventions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Pages with 1 entry",
        "Pages with entries",
        "en:US politics"
      ],
      "glosses": [
        "A political convention held during a presidential election when a political party fails to choose a nominee on the first round of delegate voting at the party's nominating convention."
      ],
      "raw_glosses": [
        "(US politics) A political convention held during a presidential election when a political party fails to choose a nominee on the first round of delegate voting at the party's nominating convention."
      ],
      "synonyms": [
        {
          "word": "open convention"
        }
      ],
      "tags": [
        "US"
      ],
      "topics": [
        "government",
        "politics"
      ]
    }
  ],
  "word": "brokered convention"
}