"NaN" meaning in English

{
  "forms": [
    {
      "form": "NaNs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "NaN (countable and uncountable, plural NaNs)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "applied to numeric values that represent an undefined or unrepresentable value, such as zero divided by itself",
          "word": "not a number"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Computing",
          "orig": "en:Computing",
          "parents": [
            "Technology",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Acronym of not a number: applied to numeric values that represent an undefined or unrepresentable value, such as zero divided by itself."
      ],
      "id": "en-NaN-en-noun-wAlNNybw",
      "links": [
        [
          "computing",
          "computing#Noun"
        ],
        [
          "not",
          "not#English"
        ],
        [
          "number",
          "number#English"
        ],
        [
          "numeric",
          "numeric"
        ],
        [
          "value",
          "value"
        ]
      ],
      "raw_glosses": [
        "(computing) Acronym of not a number: applied to numeric values that represent an undefined or unrepresentable value, such as zero divided by itself."
      ],
      "tags": [
        "abbreviation",
        "acronym",
        "alt-of",
        "countable",
        "uncountable"
      ],
      "topics": [
        "computing",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "sciences"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/næn/"
    },
    {
      "audio": "en-us-nan.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/5/5b/En-us-nan.ogg/En-us-nan.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/5/5b/En-us-nan.ogg"
    },
    {
      "rhymes": "-æn"
    },
    {
      "homophone": "nan"
    }
  ],
  "word": "NaN"
}

{
  "forms": [
    {
      "form": "NaNs",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "NaN (countable and uncountable, plural NaNs)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "applied to numeric values that represent an undefined or unrepresentable value, such as zero divided by itself",
          "word": "not a number"
        }
      ],
      "categories": [
        "English acronyms",
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English nouns",
        "English palindromes",
        "English terms with homophones",
        "English uncountable nouns",
        "Pages with 1 entry",
        "Pages with entries",
        "Rhymes:English/æn",
        "Rhymes:English/æn/1 syllable",
        "en:Computing"
      ],
      "glosses": [
        "Acronym of not a number: applied to numeric values that represent an undefined or unrepresentable value, such as zero divided by itself."
      ],
      "links": [
        [
          "computing",
          "computing#Noun"
        ],
        [
          "not",
          "not#English"
        ],
        [
          "number",
          "number#English"
        ],
        [
          "numeric",
          "numeric"
        ],
        [
          "value",
          "value"
        ]
      ],
      "raw_glosses": [
        "(computing) Acronym of not a number: applied to numeric values that represent an undefined or unrepresentable value, such as zero divided by itself."
      ],
      "tags": [
        "abbreviation",
        "acronym",
        "alt-of",
        "countable",
        "uncountable"
      ],
      "topics": [
        "computing",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "sciences"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/næn/"
    },
    {
      "audio": "en-us-nan.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/5/5b/En-us-nan.ogg/En-us-nan.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/5/5b/En-us-nan.ogg"
    },
    {
      "rhymes": "-æn"
    },
    {
      "homophone": "nan"
    }
  ],
  "word": "NaN"
}