"θ" meaning in 跨語言

{
  "categories": [
    {
      "kind": "other",
      "name": "跨語言符號",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "跨語言詞元",
      "parents": [],
      "source": "w"
    }
  ],
  "lang": "跨語言",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "glosses": [
        ":Template:幾何 平面角"
      ],
      "id": "zh-θ-mul-symbol-EERNhD28"
    },
    {
      "glosses": [
        "(國際音標) 清齒擦音"
      ],
      "id": "zh-θ-mul-symbol-tqZ8bu53"
    }
  ],
  "word": "θ"
}

{
  "categories": [
    "跨語言符號",
    "跨語言詞元"
  ],
  "lang": "跨語言",
  "lang_code": "mul",
  "pos": "symbol",
  "senses": [
    {
      "glosses": [
        ":Template:幾何 平面角"
      ]
    },
    {
      "glosses": [
        "(國際音標) 清齒擦音"
      ]
    }
  ],
  "word": "θ"
}

{
  "called_from": "extractor/zh/page/parse_section/192",
  "msg": "Unhandled subtitle: 使用注意",
  "path": [
    "θ"
  ],
  "section": "跨語言",
  "subsection": "使用注意",
  "title": "θ",
  "trace": ""
}