"500 rum" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "name": "Card games",
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      ],
      "glosses": [
        "A variant of rummy in which each player scores the value of the sets or cards they meld."
      ],
      "id": "en-500_rum-en-noun-V~7kHyBc",
      "links": [
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      "raw_glosses": [
        "(card games) A variant of rummy in which each player scores the value of the sets or cards they meld."
      ],
      "synonyms": [
        {
          "word": "500 rummy"
        },
        {
          "word": "Michigan rummy"
        },
        {
          "word": "Persian rummy"
        },
        {
          "word": "pinochle rummy"
        },
        {
          "word": "rummy 500"
        }
      ],
      "tags": [
        "uncountable"
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      "topics": [
        "card-games",
        "games"
      ]
    }
  ],
  "word": "500 rum"
}

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      "expansion": "500 rum (uncountable)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A variant of rummy in which each player scores the value of the sets or cards they meld."
      ],
      "links": [
        [
          "card game",
          "card game"
        ]
      ],
      "raw_glosses": [
        "(card games) A variant of rummy in which each player scores the value of the sets or cards they meld."
      ],
      "synonyms": [
        {
          "word": "500 rummy"
        },
        {
          "word": "Michigan rummy"
        },
        {
          "word": "Persian rummy"
        },
        {
          "word": "pinochle rummy"
        },
        {
          "word": "rummy 500"
        }
      ],
      "tags": [
        "uncountable"
      ],
      "topics": [
        "card-games",
        "games"
      ]
    }
  ],
  "word": "500 rum"
}