"19-a" meaning in Esperanto

{
  "head_templates": [
    {
      "args": {
        "1": "eo",
        "2": "adjective"
      },
      "expansion": "19-a",
      "name": "head"
    }
  ],
  "hyphenation": [
    "dek‧naŭ‧a"
  ],
  "lang": "Esperanto",
  "lang_code": "eo",
  "pos": "adj",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "19th",
          "word": "dek-naŭa"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "Esperanto entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "name": "Esperanto ordinal numbers",
          "parents": [
            "Ordinal numbers",
            "Numbers",
            "All topics",
            "Terms by semantic function",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Abbreviation of dek-naŭa (“19th”)."
      ],
      "id": "en-19-a-eo-adj-LOEIz1Ax",
      "links": [
        [
          "dek-naŭa",
          "dek-naŭa#Esperanto"
        ],
        [
          "19th",
          "19th"
        ]
      ],
      "tags": [
        "abbreviation",
        "alt-of"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[dekˈnawa]"
    },
    {
      "rhymes": "-awa"
    }
  ],
  "word": "19-a"
}

{
  "head_templates": [
    {
      "args": {
        "1": "eo",
        "2": "adjective"
      },
      "expansion": "19-a",
      "name": "head"
    }
  ],
  "hyphenation": [
    "dek‧naŭ‧a"
  ],
  "lang": "Esperanto",
  "lang_code": "eo",
  "pos": "adj",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "19th",
          "word": "dek-naŭa"
        }
      ],
      "categories": [
        "Esperanto abbreviations",
        "Esperanto adjectives",
        "Esperanto entries with incorrect language header",
        "Esperanto lemmas",
        "Esperanto multiword terms",
        "Esperanto ordinal numbers",
        "Esperanto terms spelled with numbers",
        "Esperanto terms with IPA pronunciation",
        "Esperanto terms with audio links",
        "Rhymes:Esperanto/awa"
      ],
      "glosses": [
        "Abbreviation of dek-naŭa (“19th”)."
      ],
      "links": [
        [
          "dek-naŭa",
          "dek-naŭa#Esperanto"
        ],
        [
          "19th",
          "19th"
        ]
      ],
      "tags": [
        "abbreviation",
        "alt-of"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[dekˈnawa]"
    },
    {
      "rhymes": "-awa"
    }
  ],
  "word": "19-a"
}