"crack rock" meaning in English

{
  "forms": [
    {
      "form": "crack rocks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "crack rocks"
      },
      "expansion": "crack rock (plural crack rocks)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "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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          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Recreational drugs",
          "orig": "en:Recreational drugs",
          "parents": [
            "Drugs",
            "Matter",
            "Pharmacology",
            "Chemistry",
            "Nature",
            "Biochemistry",
            "Medicine",
            "Sciences",
            "All topics",
            "Biology",
            "Healthcare",
            "Fundamental",
            "Health",
            "Body"
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          "source": "w"
        }
      ],
      "glosses": [
        "Synonym of crack cocaine"
      ],
      "id": "en-crack_rock-en-noun-VL5XC5Dd",
      "links": [
        [
          "crack cocaine",
          "crack cocaine#English"
        ]
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
            "synonym-of"
          ],
          "word": "crack cocaine"
        },
        {
          "word": "crack"
        },
        {
          "word": "crack cocaine"
        },
        {
          "word": "rock cocaine"
        }
      ]
    }
  ],
  "word": "crack rock"
}

{
  "forms": [
    {
      "form": "crack rocks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "crack rocks"
      },
      "expansion": "crack rock (plural crack rocks)",
      "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",
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        "en:Recreational drugs"
      ],
      "glosses": [
        "Synonym of crack cocaine"
      ],
      "links": [
        [
          "crack cocaine",
          "crack cocaine#English"
        ]
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
            "synonym-of"
          ],
          "word": "crack cocaine"
        }
      ]
    }
  ],
  "synonyms": [
    {
      "word": "crack"
    },
    {
      "word": "crack cocaine"
    },
    {
      "word": "rock cocaine"
    }
  ],
  "word": "crack rock"
}