"-4j" meaning in English

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          "type": "example"
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          "type": "example"
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        "Forming names of Java libraries or frameworks; for Java"
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          "for",
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          "Java",
          "Java"
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      "ipa": "/fɔː(ɹ)d͡ʒeɪ/"
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      },
      "expansion": "4 (“for”) + J (abbreviation of Java)",
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  ],
  "etymology_text": "From 4 (“for”) + J (abbreviation of Java), with the J in lowercase for stylistic reasons.",
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