"butt crack of dawn" meaning in English

{
  "etymology_text": "By the same jocular replacement as examined at ass crack of dawn § Etymology.",
  "head_templates": [
    {
      "args": {
        "1": "?",
        "head": "butt crack of dawn"
      },
      "expansion": "butt crack of dawn",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "American English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Canadian English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Times of day",
          "orig": "en:Times of day",
          "parents": [
            "Periodic occurrences",
            "Timekeeping",
            "Time",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "An intensifier, used in the same contexts as crack of dawn, but more intense."
      ],
      "id": "en-butt_crack_of_dawn-en-noun-0Wztuy-U",
      "links": [
        [
          "Canada",
          "Canada"
        ],
        [
          "US",
          "American English"
        ],
        [
          "crack of dawn",
          "crack of dawn#English"
        ]
      ],
      "raw_glosses": [
        "(Canada, US, informal) An intensifier, used in the same contexts as crack of dawn, but more intense."
      ],
      "synonyms": [
        {
          "word": "ass crack of dawn"
        },
        {
          "word": "dawn"
        }
      ],
      "tags": [
        "Canada",
        "US",
        "informal"
      ]
    }
  ],
  "word": "butt crack of dawn"
}

{
  "etymology_text": "By the same jocular replacement as examined at ass crack of dawn § Etymology.",
  "head_templates": [
    {
      "args": {
        "1": "?",
        "head": "butt crack of dawn"
      },
      "expansion": "butt crack of dawn",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "American English",
        "Canadian English",
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English nouns with unknown or uncertain plurals",
        "English terms with non-redundant non-automated sortkeys",
        "en:Times of day"
      ],
      "glosses": [
        "An intensifier, used in the same contexts as crack of dawn, but more intense."
      ],
      "links": [
        [
          "Canada",
          "Canada"
        ],
        [
          "US",
          "American English"
        ],
        [
          "crack of dawn",
          "crack of dawn#English"
        ]
      ],
      "raw_glosses": [
        "(Canada, US, informal) An intensifier, used in the same contexts as crack of dawn, but more intense."
      ],
      "tags": [
        "Canada",
        "US",
        "informal"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "ass crack of dawn"
    },
    {
      "word": "dawn"
    }
  ],
  "word": "butt crack of dawn"
}