"underextension" meaning in English

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      "expansion": "under- + extension",
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  ],
  "etymology_text": "under- + extension",
  "forms": [
    {
      "form": "underextensions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
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      "expansion": "underextension (countable and uncountable, plural underextensions)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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          "kind": "other",
          "name": "English entries with incorrect language header",
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          "orig": "en:Linguistics",
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          "source": "w"
        }
      ],
      "coordinate_terms": [
        {
          "word": "overextension"
        }
      ],
      "glosses": [
        "Application of a term to too few referents, as for example when a child uses cat to refer only to the family pet."
      ],
      "id": "en-underextension-en-noun-sqAYy5Wd",
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      "raw_glosses": [
        "(linguistics) Application of a term to too few referents, as for example when a child uses cat to refer only to the family pet."
      ],
      "tags": [
        "countable",
        "uncountable"
      ],
      "topics": [
        "human-sciences",
        "linguistics",
        "sciences"
      ]
    }
  ],
  "word": "underextension"
}

{
  "coordinate_terms": [
    {
      "word": "overextension"
    }
  ],
  "etymology_templates": [
    {
      "args": {
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        "2": "under",
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  ],
  "etymology_text": "under- + extension",
  "forms": [
    {
      "form": "underextensions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
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      "expansion": "underextension (countable and uncountable, plural underextensions)",
      "name": "en-noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
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      "glosses": [
        "Application of a term to too few referents, as for example when a child uses cat to refer only to the family pet."
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        "(linguistics) Application of a term to too few referents, as for example when a child uses cat to refer only to the family pet."
      ],
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        "uncountable"
      ],
      "topics": [
        "human-sciences",
        "linguistics",
        "sciences"
      ]
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  ],
  "word": "underextension"
}