"-4j" meaning in English

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  "etymology_text": "4 (“for”) + J (abbreviation of Java), with the J in lowercase for stylistic reasons.",
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  "lang_code": "en",
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          "type": "example"
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          "text": "couchdb4j",
          "type": "example"
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        "Forming names of Java libraries or frameworks; for Java"
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        [
          "for",
          "for"
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          "Java",
          "Java"
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        {
          "word": "-4J"
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  "sounds": [
    {
      "ipa": "/fɔː(ɹ) d͡ʒeɪ/"
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  "word": "-4j"
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        "2": "4",
        "3": "J",
        "pos2": "abbreviation of <i class=\"Latn mention\" lang=\"en\">Java</i>",
        "t1": "for"
      },
      "expansion": "4 (“for”) + J (abbreviation of Java)",
      "name": "affix"
    },
    {
      "args": {
        "1": "en",
        "2": "",
        "3": "J"
      },
      "expansion": "J",
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  ],
  "etymology_text": "4 (“for”) + J (abbreviation of Java), with the J in lowercase for stylistic reasons.",
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          "text": "Log4j",
          "type": "example"
        },
        {
          "text": "couchdb4j",
          "type": "example"
        }
      ],
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        "Forming names of Java libraries or frameworks; for Java"
      ],
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  "synonyms": [
    {
      "word": "-4J"
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  "word": "-4j"
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