"nails on a chalkboard" meaning in English

{
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      "expansion": "nails on a chalkboard (uncountable)",
      "name": "en-noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "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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      "examples": [
        {
          "ref": "2000 May 2, Christopher John, “country singers who turned to acting”, in rec.music.country.western (Usenet)",
          "text": "That's funny because I hated Randy's voice until I saw that movie. It was nails on a chalkboard until I heard \"My Greatest Fear\" that song is very pretty, IMO.",
          "type": "quotation"
        },
        {
          "ref": "2001 February 17, mrs_cal, “Why do you post here?”, in alt.support.divorce (Usenet)",
          "text": "aside from country music (which is nails on a chalkboard to me, lol) and what my son and I call 'pop drivel a la Backstreet Boys, and N'Stink.....I will listen to, and probably enjoy most anything.",
          "type": "quotation"
        },
        {
          "ref": "2005 December 6, Nancy Young, “Way OT: Phrases you hate”, in rec.food.cooking (Usenet)",
          "text": "[The phrase] Where's it at? is nails on a chalkboard to me, but I am sure I have many annoying speech mannerisms, too.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Something that sounds very unpleasant."
      ],
      "id": "en-nails_on_a_chalkboard-en-noun-hNO13nE2",
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "nails on a chalkboard"
}

{
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "nails on a chalkboard (uncountable)",
      "name": "en-noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations",
        "English uncountable nouns"
      ],
      "examples": [
        {
          "ref": "2000 May 2, Christopher John, “country singers who turned to acting”, in rec.music.country.western (Usenet)",
          "text": "That's funny because I hated Randy's voice until I saw that movie. It was nails on a chalkboard until I heard \"My Greatest Fear\" that song is very pretty, IMO.",
          "type": "quotation"
        },
        {
          "ref": "2001 February 17, mrs_cal, “Why do you post here?”, in alt.support.divorce (Usenet)",
          "text": "aside from country music (which is nails on a chalkboard to me, lol) and what my son and I call 'pop drivel a la Backstreet Boys, and N'Stink.....I will listen to, and probably enjoy most anything.",
          "type": "quotation"
        },
        {
          "ref": "2005 December 6, Nancy Young, “Way OT: Phrases you hate”, in rec.food.cooking (Usenet)",
          "text": "[The phrase] Where's it at? is nails on a chalkboard to me, but I am sure I have many annoying speech mannerisms, too.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Something that sounds very unpleasant."
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "word": "nails on a chalkboard"
}