"pre-oxidation" meaning in English

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      "expansion": "pre-oxidation",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "preoxidation"
        }
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          "source": "w"
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      ],
      "glosses": [
        "Alternative form of preoxidation"
      ],
      "id": "en-pre-oxidation-en-noun-a1cAcwUa",
      "links": [
        [
          "preoxidation",
          "preoxidation#English"
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      "tags": [
        "alt-of",
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    }
  ],
  "word": "pre-oxidation"
}

{
  "head_templates": [
    {
      "args": {
        "1": "?"
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      "expansion": "pre-oxidation",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "preoxidation"
        }
      ],
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English nouns with unknown or uncertain plurals"
      ],
      "glosses": [
        "Alternative form of preoxidation"
      ],
      "links": [
        [
          "preoxidation",
          "preoxidation#English"
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      "tags": [
        "alt-of",
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  ],
  "word": "pre-oxidation"
}