"whack shack" meaning in English

{
  "forms": [
    {
      "form": "whack shacks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "whack shack (plural whack shacks)",
      "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",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with language name categories using raw markup",
          "parents": [
            "Entries with language name categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English rhyming compounds",
          "parents": [
            "Rhyming compounds",
            "Compound terms",
            "Rhyming phrases",
            "Terms by etymology",
            "Phrases",
            "Lemmas"
          ],
          "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"
        }
      ],
      "glosses": [
        "Mental hospital."
      ],
      "id": "en-whack_shack-en-noun-Pdb5sPNT",
      "links": [
        [
          "Mental hospital",
          "mental hospital"
        ]
      ],
      "raw_glosses": [
        "(slang) Mental hospital."
      ],
      "synonyms": [
        {
          "word": "wack shack"
        }
      ],
      "tags": [
        "slang"
      ]
    }
  ],
  "word": "whack shack"
}

{
  "forms": [
    {
      "form": "whack shacks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "whack shack (plural whack shacks)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with language name categories using raw markup",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English rhyming compounds",
        "English slang",
        "English terms with non-redundant non-automated sortkeys"
      ],
      "glosses": [
        "Mental hospital."
      ],
      "links": [
        [
          "Mental hospital",
          "mental hospital"
        ]
      ],
      "raw_glosses": [
        "(slang) Mental hospital."
      ],
      "tags": [
        "slang"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "wack shack"
    }
  ],
  "word": "whack shack"
}