"mg" meaning in 跨语言

{
  "categories": [
    {
      "kind": "other",
      "name": "有1個詞條的頁面",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "有詞條的頁面",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "跨語言符號",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "跨語言詞元",
      "parents": [],
      "source": "w"
    }
  ],
  "lang": "跨语言",
  "lang_code": "mul",
  "pos": "symbol",
  "pos_title": "符号",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "跨語言 度量衡學",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "毫克（milligram）國際單位制符號"
      ],
      "id": "zh-mg-mul-symbol-gw-HSZ1D",
      "topics": [
        "metrology"
      ]
    },
    {
      "glosses": [
        "馬拉加斯語的ISO639-1語言代碼"
      ],
      "id": "zh-mg-mul-symbol-i2syrYK7"
    }
  ],
  "word": "mg"
}

{
  "categories": [
    "有1個詞條的頁面",
    "有詞條的頁面",
    "跨語言符號",
    "跨語言詞元"
  ],
  "lang": "跨语言",
  "lang_code": "mul",
  "pos": "symbol",
  "pos_title": "符号",
  "senses": [
    {
      "categories": [
        "跨語言 度量衡學"
      ],
      "glosses": [
        "毫克（milligram）國際單位制符號"
      ],
      "topics": [
        "metrology"
      ]
    },
    {
      "glosses": [
        "馬拉加斯語的ISO639-1語言代碼"
      ]
    }
  ],
  "word": "mg"
}