"one fifth" meaning in English

{
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      "expansion": "one fifth",
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "num",
  "senses": [
    {
      "alt_of": [
        {
          "word": "one-fifth"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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            "Entry maintenance"
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          "source": "w"
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      ],
      "glosses": [
        "rare spelling of one-fifth"
      ],
      "id": "en-one_fifth-en-num-CPn38bPu",
      "links": [
        [
          "one-fifth",
          "one-fifth#English"
        ]
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      "tags": [
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  ],
  "word": "one fifth"
}

{
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "numeral"
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      "expansion": "one fifth",
      "name": "head"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "num",
  "senses": [
    {
      "alt_of": [
        {
          "word": "one-fifth"
        }
      ],
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        "English lemmas",
        "English multiword terms",
        "English numerals"
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      "glosses": [
        "rare spelling of one-fifth"
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      "links": [
        [
          "one-fifth",
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      "tags": [
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  ],
  "word": "one fifth"
}

{
  "called_from": "form_descriptions/1698",
  "msg": "unrecognized head form: 1/5",
  "path": [
    "one fifth"
  ],
  "section": "English",
  "subsection": "numeral",
  "title": "one fifth",
  "trace": ""
}