"lunar letter" meaning in English

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        "3": "حَرْف قَمَرِيّ"
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      "expansion": "Calque of Arabic حَرْف قَمَرِيّ (ḥarf qamariyy)",
      "name": "calque"
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  "etymology_text": "Calque of Arabic حَرْف قَمَرِيّ (ḥarf qamariyy).",
  "forms": [
    {
      "form": "lunar letters",
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Synonym of moon letter"
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      "id": "en-lunar_letter-en-noun-4r3YfHOy",
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      "synonyms": [
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          "word": "moon letter"
        }
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      "wikipedia": [
        "Moon letters"
      ]
    }
  ],
  "word": "lunar letter"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "ar",
        "3": "حَرْف قَمَرِيّ"
      },
      "expansion": "Calque of Arabic حَرْف قَمَرِيّ (ḥarf qamariyy)",
      "name": "calque"
    }
  ],
  "etymology_text": "Calque of Arabic حَرْف قَمَرِيّ (ḥarf qamariyy).",
  "forms": [
    {
      "form": "lunar letters",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
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        "Synonym of moon letter"
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  "word": "lunar letter"
}