"30." meaning in Icelandic

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  "lang": "Icelandic",
  "lang_code": "is",
  "pos": "adj",
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      "synonyms": [
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          "tags": [
            "masculine"
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          "word": "þrítugasti"
        },
        {
          "tags": [
            "feminine",
            "neuter"
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          "word": "þrítugasta"
        }
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  "word": "30."
}

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  "pos": "adj",
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        "30th"
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  "synonyms": [
    {
      "tags": [
        "masculine"
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      "word": "þrítugasti"
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    {
      "tags": [
        "feminine",
        "neuter"
      ],
      "word": "þrítugasta"
    }
  ],
  "word": "30."
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  "msg": "unrecognized linkage prefix: (30th): þrítugasti m, þrítugasta f or n desc=30th rest=þrítugasti m, þrítugasta f or n cls=romanization cls2=romanization e1=True e2=False",
  "path": [
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  "subsection": "adjective",
  "title": "30.",
  "trace": ""
}