"0-dark-hundred" meaning in English

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      "expansion": "0-dark-hundred (uncountable)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "name": "American English",
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          "kind": "topical",
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          "name": "Times of day",
          "orig": "en:Times of day",
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      "examples": [
        {
          "ref": "1996, Richard Marcinko, John Weisman, Green Team: Rogue Warrior III, page 4",
          "text": "Which is precisely why I'd volunteered as point man on this little jaunt, prowling and growling up the unlit stairwell of a Cairo slum at 0-dark-hundred to catch my quarry napping on his bedroll.",
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          "ref": "2011, Diane L. Sheridan, Don't Forget the Flippin' E: A Memoir, page 290",
          "text": "It's late, and we have to get up at 0-dark-hundred to got to Paris in the AM.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "An otherwise unspecified time of night; some time when it is dark out."
      ],
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      "raw_glosses": [
        "(chiefly US military slang) An otherwise unspecified time of night; some time when it is dark out."
      ],
      "related": [
        {
          "word": "0-dark-thirty"
        },
        {
          "word": "dark thirty"
        },
        {
          "word": "oh dark hundred"
        },
        {
          "word": "oh dark thirty"
        },
        {
          "word": "zero dark thirty"
        },
        {
          "word": "beer o'clock"
        }
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      "synonyms": [
        {
          "word": "stupid o'clock"
        },
        {
          "word": "wee small hours"
        },
        {
          "word": "early morning"
        }
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      "tags": [
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      "topics": [
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  "word": "0-dark-hundred"
}

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "0-dark-thirty"
    },
    {
      "word": "dark thirty"
    },
    {
      "word": "oh dark hundred"
    },
    {
      "word": "oh dark thirty"
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    {
      "word": "zero dark thirty"
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    {
      "word": "beer o'clock"
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          "ref": "1996, Richard Marcinko, John Weisman, Green Team: Rogue Warrior III, page 4",
          "text": "Which is precisely why I'd volunteered as point man on this little jaunt, prowling and growling up the unlit stairwell of a Cairo slum at 0-dark-hundred to catch my quarry napping on his bedroll.",
          "type": "quotation"
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        {
          "ref": "2011, Diane L. Sheridan, Don't Forget the Flippin' E: A Memoir, page 290",
          "text": "It's late, and we have to get up at 0-dark-hundred to got to Paris in the AM.",
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      ],
      "glosses": [
        "An otherwise unspecified time of night; some time when it is dark out."
      ],
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          "slang",
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        "(chiefly US military slang) An otherwise unspecified time of night; some time when it is dark out."
      ],
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  "synonyms": [
    {
      "word": "stupid o'clock"
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    {
      "word": "wee small hours"
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    {
      "word": "early morning"
    }
  ],
  "word": "0-dark-hundred"
}