"nundinal letter" meaning in English

{
  "forms": [
    {
      "form": "nundinal letters",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "nundinal letter (plural nundinal letters)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
        },
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          "kind": "topical",
          "langcode": "en",
          "name": "Ancient Rome",
          "orig": "en:Ancient Rome",
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            "Ancient Europe",
            "Ancient history",
            "Ancient Near East",
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          "source": "w"
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          "kind": "topical",
          "langcode": "en",
          "name": "Letters",
          "orig": "en:Letters",
          "parents": [
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            "Symbols",
            "Letters, symbols, and punctuation",
            "Orthography",
            "Writing",
            "Human behaviour",
            "Language",
            "Human",
            "Communication",
            "All topics"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "one of the first eight letters of the alphabet, repeated successively from the first to the last day of the year. One of these always corresponded to the market day, which occurred every eight days."
      ],
      "id": "en-nundinal_letter-en-noun-G3HuCEkR",
      "links": [
        [
          "Ancient Rome",
          "Ancient Rome"
        ],
        [
          "letter",
          "letter"
        ],
        [
          "alphabet",
          "alphabet"
        ],
        [
          "market",
          "market"
        ]
      ],
      "raw_glosses": [
        "(Ancient Rome) one of the first eight letters of the alphabet, repeated successively from the first to the last day of the year. One of these always corresponded to the market day, which occurred every eight days."
      ],
      "tags": [
        "Ancient-Rome"
      ]
    }
  ],
  "word": "nundinal letter"
}

{
  "forms": [
    {
      "form": "nundinal letters",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "nundinal letter (plural nundinal letters)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "en:Ancient Rome",
        "en:Letters"
      ],
      "glosses": [
        "one of the first eight letters of the alphabet, repeated successively from the first to the last day of the year. One of these always corresponded to the market day, which occurred every eight days."
      ],
      "links": [
        [
          "Ancient Rome",
          "Ancient Rome"
        ],
        [
          "letter",
          "letter"
        ],
        [
          "alphabet",
          "alphabet"
        ],
        [
          "market",
          "market"
        ]
      ],
      "raw_glosses": [
        "(Ancient Rome) one of the first eight letters of the alphabet, repeated successively from the first to the last day of the year. One of these always corresponded to the market day, which occurred every eight days."
      ],
      "tags": [
        "Ancient-Rome"
      ]
    }
  ],
  "word": "nundinal letter"
}