"R0" meaning in Translingual

{
  "etymology_templates": [
    {
      "args": {
        "1": "mul",
        "2": "en",
        "3": "reproduction",
        "gloss": "R"
      },
      "expansion": "English reproduction (“R”)",
      "name": "der"
    }
  ],
  "etymology_text": "From English reproduction (“R”) + zero (“0”).",
  "forms": [
    {
      "form": "R₀",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "2": "noun",
        "head": "R₀"
      },
      "expansion": "R₀",
      "name": "head"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 2 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Translingual entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "mul",
          "name": "Epidemiology",
          "orig": "mul:Epidemiology",
          "parents": [
            "Medicine",
            "Biology",
            "Healthcare",
            "Sciences",
            "Health",
            "All topics",
            "Body",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "The basic reproduction ratio"
      ],
      "id": "en-R0-mul-noun-OJ-38L5z",
      "links": [
        [
          "epidemiology",
          "epidemiology"
        ],
        [
          "basic reproduction ratio",
          "basic reproduction ratio"
        ]
      ],
      "raw_glosses": [
        "(epidemiology) The basic reproduction ratio"
      ],
      "synonyms": [
        {
          "word": "R₀"
        },
        {
          "word": "R-0"
        }
      ],
      "topics": [
        "epidemiology",
        "medicine",
        "sciences"
      ]
    }
  ],
  "word": "R0"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "mul",
        "2": "en",
        "3": "reproduction",
        "gloss": "R"
      },
      "expansion": "English reproduction (“R”)",
      "name": "der"
    }
  ],
  "etymology_text": "From English reproduction (“R”) + zero (“0”).",
  "forms": [
    {
      "form": "R₀",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "2": "noun",
        "head": "R₀"
      },
      "expansion": "R₀",
      "name": "head"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Pages with 2 entries",
        "Pages with entries",
        "Translingual entries with incorrect language header",
        "Translingual lemmas",
        "Translingual nouns",
        "Translingual terms derived from English",
        "Translingual terms spelled with numbers",
        "mul:Epidemiology"
      ],
      "glosses": [
        "The basic reproduction ratio"
      ],
      "links": [
        [
          "epidemiology",
          "epidemiology"
        ],
        [
          "basic reproduction ratio",
          "basic reproduction ratio"
        ]
      ],
      "raw_glosses": [
        "(epidemiology) The basic reproduction ratio"
      ],
      "topics": [
        "epidemiology",
        "medicine",
        "sciences"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "R₀"
    },
    {
      "word": "R-0"
    }
  ],
  "word": "R0"
}