"Na" meaning in Translingual

{
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    {
      "args": {
        "1": "mul",
        "2": "la",
        "3": "natrium"
      },
      "expansion": "Latin natrium",
      "name": "der"
    }
  ],
  "etymology_text": "From Latin natrium.",
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "2": "symbol"
      },
      "expansion": "Na",
      "name": "head"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 3 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Symbols for chemical elements",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Translingual entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "langcode": "mul",
          "name": "Alkali metals",
          "orig": "mul:Alkali metals",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Chemical symbol for sodium."
      ],
      "id": "en-Na-mul-symbol-lodgXGwS",
      "links": [
        [
          "chemistry",
          "chemistry"
        ],
        [
          "sodium",
          "sodium#English"
        ]
      ],
      "raw_glosses": [
        "(chemistry) Chemical symbol for sodium."
      ],
      "topics": [
        "chemistry",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "Na"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "mul",
        "2": "la",
        "3": "natrium"
      },
      "expansion": "Latin natrium",
      "name": "der"
    }
  ],
  "etymology_text": "From Latin natrium.",
  "head_templates": [
    {
      "args": {
        "1": "mul",
        "2": "symbol"
      },
      "expansion": "Na",
      "name": "head"
    }
  ],
  "lang": "Translingual",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "categories": [
        "Pages with 3 entries",
        "Pages with entries",
        "Symbols for chemical elements",
        "Translingual entries with incorrect language header",
        "Translingual lemmas",
        "Translingual symbols",
        "Translingual terms derived from Latin",
        "mul:Alkali metals"
      ],
      "glosses": [
        "Chemical symbol for sodium."
      ],
      "links": [
        [
          "chemistry",
          "chemistry"
        ],
        [
          "sodium",
          "sodium#English"
        ]
      ],
      "raw_glosses": [
        "(chemistry) Chemical symbol for sodium."
      ],
      "topics": [
        "chemistry",
        "natural-sciences",
        "physical-sciences"
      ]
    }
  ],
  "word": "Na"
}