"ꟿ" meaning in Latin

{
  "etymology_text": "*An archaic form of the letter M retained specifically as an abbreviation of this name.",
  "head_templates": [
    {
      "args": {
        "1": "ꟿ",
        "g": "m",
        "indecl": "1"
      },
      "expansion": "ꟿ m (indeclinable)",
      "name": "la-proper noun"
    }
  ],
  "lang": "Latin",
  "lang_code": "la",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Manius"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "Latin entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Praenominal abbreviation of Manius."
      ],
      "id": "en-ꟿ-la-name-Zw-U7ww~",
      "links": [
        [
          "Praenominal",
          "praenomen#English"
        ],
        [
          "Manius",
          "Manius#Latin"
        ]
      ],
      "synonyms": [
        {
          "english": "a modern typographic substitution",
          "word": "M'"
        }
      ],
      "tags": [
        "Praenominal",
        "abbreviation",
        "alt-of",
        "indeclinable",
        "masculine"
      ]
    }
  ],
  "word": "ꟿ"
}

{
  "etymology_text": "*An archaic form of the letter M retained specifically as an abbreviation of this name.",
  "head_templates": [
    {
      "args": {
        "1": "ꟿ",
        "g": "m",
        "indecl": "1"
      },
      "expansion": "ꟿ m (indeclinable)",
      "name": "la-proper noun"
    }
  ],
  "lang": "Latin",
  "lang_code": "la",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Manius"
        }
      ],
      "categories": [
        "Latin abbreviations",
        "Latin entries with incorrect language header",
        "Latin indeclinable nouns",
        "Latin lemmas",
        "Latin masculine indeclinable nouns",
        "Latin masculine nouns",
        "Latin praenominal abbreviations",
        "Latin proper nouns"
      ],
      "glosses": [
        "Praenominal abbreviation of Manius."
      ],
      "links": [
        [
          "Praenominal",
          "praenomen#English"
        ],
        [
          "Manius",
          "Manius#Latin"
        ]
      ],
      "tags": [
        "Praenominal",
        "abbreviation",
        "alt-of",
        "indeclinable",
        "masculine"
      ]
    }
  ],
  "synonyms": [
    {
      "english": "a modern typographic substitution",
      "word": "M'"
    }
  ],
  "word": "ꟿ"
}