"someone's number is up" meaning in English

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      "expansion": "someone's number is up",
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  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
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          "source": "w"
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      ],
      "examples": [
        {
          "ref": "2014 December 16, Fujino Omori, Is It Wrong to Try to Pick Up Girls in a Dungeon?, Vol. 1 (light novel), Yen Press LLC",
          "text": "Even in this hopeless situation, I don't feel like my number's up. I have to reach the next level, get closer to her. I don't have time to play with the monsters down here. I'm in the eye of a storm of howls and roars, but I'm different[…]",
          "type": "quotation"
        },
        {
          "ref": "2012 July 3, DW Gibson, Not Working: People Talk About Losing a Job and Finding Their Way in Today's Changing Economy, Penguin",
          "text": "So I just thought, well, my number's up. I'm going to get some stupid assignment that nobody wants.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "It is someone's time to die, or to undergo some other difficult experience."
      ],
      "id": "en-someone's_number_is_up-en-phrase-MgN380m3",
      "links": [
        [
          "die",
          "die"
        ]
      ],
      "raw_glosses": [
        "(informal) It is someone's time to die, or to undergo some other difficult experience."
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "word": "someone's number is up"
}

{
  "head_templates": [
    {
      "args": {
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        "2": "phrase"
      },
      "expansion": "someone's number is up",
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  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English phrases",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "2014 December 16, Fujino Omori, Is It Wrong to Try to Pick Up Girls in a Dungeon?, Vol. 1 (light novel), Yen Press LLC",
          "text": "Even in this hopeless situation, I don't feel like my number's up. I have to reach the next level, get closer to her. I don't have time to play with the monsters down here. I'm in the eye of a storm of howls and roars, but I'm different[…]",
          "type": "quotation"
        },
        {
          "ref": "2012 July 3, DW Gibson, Not Working: People Talk About Losing a Job and Finding Their Way in Today's Changing Economy, Penguin",
          "text": "So I just thought, well, my number's up. I'm going to get some stupid assignment that nobody wants.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "It is someone's time to die, or to undergo some other difficult experience."
      ],
      "links": [
        [
          "die",
          "die"
        ]
      ],
      "raw_glosses": [
        "(informal) It is someone's time to die, or to undergo some other difficult experience."
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "word": "someone's number is up"
}