"what's the use" meaning in English

{
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      "expansion": "what's the use",
      "name": "head"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
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      "examples": [
        {
          "text": "What's the use trying to tell him? He won't listen.",
          "type": "example"
        },
        {
          "text": "What's the use of worrying? It never was worthwhile.",
          "type": "example"
        }
      ],
      "glosses": [
        "Used to indicate that a specified or implied action cannot succeed or offers no advantage if successful"
      ],
      "id": "en-what's_the_use-en-phrase-NJ2bAdpL",
      "raw_glosses": [
        "(colloquial, often with a following present participle or infinitive expression) Used to indicate that a specified or implied action cannot succeed or offers no advantage if successful"
      ],
      "raw_tags": [
        "with a following present participle or infinitive expression"
      ],
      "related": [
        {
          "word": "there's no use"
        },
        {
          "word": "no use"
        },
        {
          "word": "it's no use"
        }
      ],
      "tags": [
        "colloquial",
        "often"
      ]
    }
  ],
  "word": "what's the use"
}

{
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "phrase"
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      "expansion": "what's the use",
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "related": [
    {
      "word": "there's no use"
    },
    {
      "word": "no use"
    },
    {
      "word": "it's no use"
    }
  ],
  "senses": [
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        "English colloquialisms",
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      "examples": [
        {
          "text": "What's the use trying to tell him? He won't listen.",
          "type": "example"
        },
        {
          "text": "What's the use of worrying? It never was worthwhile.",
          "type": "example"
        }
      ],
      "glosses": [
        "Used to indicate that a specified or implied action cannot succeed or offers no advantage if successful"
      ],
      "raw_glosses": [
        "(colloquial, often with a following present participle or infinitive expression) Used to indicate that a specified or implied action cannot succeed or offers no advantage if successful"
      ],
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        "with a following present participle or infinitive expression"
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        "colloquial",
        "often"
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  ],
  "word": "what's the use"
}