"nghịch đảo" meaning in Vietnamese

{
  "etymology_templates": [
    {
      "args": {
        "1": "vi",
        "2": "逆",
        "t": ""
      },
      "expansion": "逆",
      "name": "m"
    },
    {
      "args": {
        "1": "vi",
        "2": "倒",
        "t": ""
      },
      "expansion": "倒",
      "name": "m"
    },
    {
      "args": {
        "1": "vi",
        "2": "Sino-Vietnamese words"
      },
      "expansion": "",
      "name": "categorize"
    },
    {
      "args": {
        "1": "逆",
        "2": "",
        "3": "倒"
      },
      "expansion": "Sino-Vietnamese word from 逆 and 倒",
      "name": "vi-etym-sino"
    }
  ],
  "etymology_text": "Sino-Vietnamese word from 逆 and 倒",
  "head_templates": [
    {
      "args": {
        "1": "vi",
        "2": "adjective",
        "3": "",
        "4": "",
        "5": "",
        "6": "",
        "head": "",
        "tr": ""
      },
      "expansion": "nghịch đảo",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "nghịch đảo",
      "name": "vi-adj"
    }
  ],
  "lang": "Vietnamese",
  "lang_code": "vi",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Sino-Vietnamese words",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Sino-Vietnamese words with uncreated Han etymology",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Vietnamese entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "vi",
          "name": "Mathematics",
          "orig": "vi:Mathematics",
          "parents": [
            "Formal sciences",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "inverse"
      ],
      "id": "en-nghịch_đảo-vi-adj-dwWszSaU",
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "inverse",
          "inverse"
        ]
      ],
      "raw_glosses": [
        "(mathematics) inverse"
      ],
      "topics": [
        "mathematics",
        "sciences"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[ŋïk̟̚˧˨ʔ ʔɗaːw˧˩]",
      "tags": [
        "Hà-Nội"
      ]
    },
    {
      "ipa": "[ŋɨt̚˨˩ʔ ʔɗaːw˧˨]",
      "tags": [
        "Huế"
      ]
    },
    {
      "ipa": "[ŋɨt̚˨˩˨ ʔɗaːw˨˩˦]",
      "tags": [
        "Hồ-Chí-Minh-City"
      ]
    }
  ],
  "word": "nghịch đảo"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "vi",
        "2": "逆",
        "t": ""
      },
      "expansion": "逆",
      "name": "m"
    },
    {
      "args": {
        "1": "vi",
        "2": "倒",
        "t": ""
      },
      "expansion": "倒",
      "name": "m"
    },
    {
      "args": {
        "1": "vi",
        "2": "Sino-Vietnamese words"
      },
      "expansion": "",
      "name": "categorize"
    },
    {
      "args": {
        "1": "逆",
        "2": "",
        "3": "倒"
      },
      "expansion": "Sino-Vietnamese word from 逆 and 倒",
      "name": "vi-etym-sino"
    }
  ],
  "etymology_text": "Sino-Vietnamese word from 逆 and 倒",
  "head_templates": [
    {
      "args": {
        "1": "vi",
        "2": "adjective",
        "3": "",
        "4": "",
        "5": "",
        "6": "",
        "head": "",
        "tr": ""
      },
      "expansion": "nghịch đảo",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "nghịch đảo",
      "name": "vi-adj"
    }
  ],
  "lang": "Vietnamese",
  "lang_code": "vi",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "Sino-Vietnamese words",
        "Sino-Vietnamese words with uncreated Han etymology",
        "Vietnamese adjectives",
        "Vietnamese entries with incorrect language header",
        "Vietnamese lemmas",
        "Vietnamese terms with IPA pronunciation",
        "vi:Mathematics"
      ],
      "glosses": [
        "inverse"
      ],
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "inverse",
          "inverse"
        ]
      ],
      "raw_glosses": [
        "(mathematics) inverse"
      ],
      "topics": [
        "mathematics",
        "sciences"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[ŋïk̟̚˧˨ʔ ʔɗaːw˧˩]",
      "tags": [
        "Hà-Nội"
      ]
    },
    {
      "ipa": "[ŋɨt̚˨˩ʔ ʔɗaːw˧˨]",
      "tags": [
        "Huế"
      ]
    },
    {
      "ipa": "[ŋɨt̚˨˩˨ ʔɗaːw˨˩˦]",
      "tags": [
        "Hồ-Chí-Minh-City"
      ]
    }
  ],
  "word": "nghịch đảo"
}