"sis boom bah" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en"
      },
      "expansion": "Onomatopoeic",
      "name": "onomatopoeic"
    }
  ],
  "etymology_text": "Onomatopoeic",
  "head_templates": [
    {
      "args": {
        "nolinkhead": "1"
      },
      "expansion": "sis boom bah",
      "name": "en-interj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "American English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Cheerleading",
          "orig": "en:Cheerleading",
          "parents": [
            "Dance",
            "Gymnastics",
            "Sports",
            "Art",
            "Recreation",
            "Human activity",
            "Culture",
            "Human behaviour",
            "Society",
            "Human",
            "All topics",
            "Fundamental"
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          "source": "w"
        },
        {
          "_dis": "88 12",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w+disamb"
        },
        {
          "_dis": "86 14",
          "kind": "other",
          "name": "English onomatopoeias",
          "parents": [],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "An exclamation of encouragement."
      ],
      "id": "en-sis_boom_bah-en-intj-W1sIyQcX",
      "links": [
        [
          "cheerleading",
          "cheerleading#Noun"
        ],
        [
          "exclamation",
          "exclamation#English"
        ],
        [
          "encouragement",
          "encouragement#English"
        ]
      ],
      "raw_glosses": [
        "(US, cheerleading) An exclamation of encouragement."
      ],
      "related": [
        {
          "_dis1": "62 38",
          "word": "cheering"
        }
      ],
      "synonyms": [
        {
          "word": "hooray"
        },
        {
          "word": "hurrah"
        },
        {
          "word": "hurray"
        },
        {
          "word": "huzzah"
        }
      ],
      "tags": [
        "US"
      ],
      "topics": [
        "cheerleading",
        "hobbies",
        "lifestyle",
        "sports"
      ]
    },
    {
      "categories": [],
      "glosses": [
        "The characteristic sound made by fireworks."
      ],
      "id": "en-sis_boom_bah-en-intj-5O7wZ3jg",
      "links": [
        [
          "fireworks",
          "fireworks#English"
        ]
      ],
      "raw_glosses": [
        "(dated) The characteristic sound made by fireworks."
      ],
      "tags": [
        "dated"
      ]
    }
  ],
  "sounds": [
    {
      "rhymes": "-ɑː"
    }
  ],
  "word": "sis boom bah"
}

{
  "categories": [
    "English entries with incorrect language header",
    "English interjections",
    "English lemmas",
    "English multiword terms",
    "English onomatopoeias",
    "Rhymes:English/ɑː"
  ],
  "etymology_templates": [
    {
      "args": {
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      "expansion": "Onomatopoeic",
      "name": "onomatopoeic"
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  ],
  "etymology_text": "Onomatopoeic",
  "head_templates": [
    {
      "args": {
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      },
      "expansion": "sis boom bah",
      "name": "en-interj"
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  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "related": [
    {
      "word": "cheering"
    }
  ],
  "senses": [
    {
      "categories": [
        "American English",
        "en:Cheerleading"
      ],
      "glosses": [
        "An exclamation of encouragement."
      ],
      "links": [
        [
          "cheerleading",
          "cheerleading#Noun"
        ],
        [
          "exclamation",
          "exclamation#English"
        ],
        [
          "encouragement",
          "encouragement#English"
        ]
      ],
      "raw_glosses": [
        "(US, cheerleading) An exclamation of encouragement."
      ],
      "synonyms": [
        {
          "word": "hooray"
        },
        {
          "word": "hurrah"
        },
        {
          "word": "hurray"
        },
        {
          "word": "huzzah"
        }
      ],
      "tags": [
        "US"
      ],
      "topics": [
        "cheerleading",
        "hobbies",
        "lifestyle",
        "sports"
      ]
    },
    {
      "categories": [
        "English dated terms"
      ],
      "glosses": [
        "The characteristic sound made by fireworks."
      ],
      "links": [
        [
          "fireworks",
          "fireworks#English"
        ]
      ],
      "raw_glosses": [
        "(dated) The characteristic sound made by fireworks."
      ],
      "tags": [
        "dated"
      ]
    }
  ],
  "sounds": [
    {
      "rhymes": "-ɑː"
    }
  ],
  "word": "sis boom bah"
}