"know backwards" meaning in All languages combined

{
  "etymology_text": "Suggesting such familiarity with something that one could recite or list it even in reverse order.",
  "forms": [
    {
      "form": "knows backwards",
      "tags": [
        "present",
        "singular",
        "third-person"
      ]
    },
    {
      "form": "knowing backwards",
      "tags": [
        "participle",
        "present"
      ]
    },
    {
      "form": "knew backwards",
      "tags": [
        "past"
      ]
    },
    {
      "form": "known backwards",
      "tags": [
        "participle",
        "past"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "know<,,knew,known> backwards"
      },
      "expansion": "know backwards (third-person singular simple present knows backwards, present participle knowing backwards, simple past knew backwards, past participle known backwards)",
      "name": "en-verb"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "British English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Danish translations",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "To have very thorough knowledge of."
      ],
      "id": "en-know_backwards-en-verb-q4eBpO4I",
      "links": [
        [
          "thorough",
          "thorough"
        ],
        [
          "knowledge",
          "knowledge"
        ]
      ],
      "raw_glosses": [
        "(UK, transitive) To have very thorough knowledge of."
      ],
      "synonyms": [
        {
          "word": "know inside and out"
        },
        {
          "word": "know backward and forward"
        },
        {
          "tags": [
            "US"
          ],
          "word": "know backwards and forwards"
        },
        {
          "tags": [
            "UK",
            "US"
          ],
          "word": "know back to front"
        }
      ],
      "tags": [
        "UK",
        "transitive"
      ],
      "translations": [
        {
          "code": "da",
          "lang": "Danish",
          "sense": "have a very thorough knowledge",
          "word": "have dyb kundskab"
        }
      ]
    }
  ],
  "sounds": [
    {
      "audio": "LL-Q1860 (eng)-Flame, not lame-know backwards.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/9/94/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/9/94/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav.ogg"
    }
  ],
  "word": "know backwards"
}

{
  "etymology_text": "Suggesting such familiarity with something that one could recite or list it even in reverse order.",
  "forms": [
    {
      "form": "knows backwards",
      "tags": [
        "present",
        "singular",
        "third-person"
      ]
    },
    {
      "form": "knowing backwards",
      "tags": [
        "participle",
        "present"
      ]
    },
    {
      "form": "knew backwards",
      "tags": [
        "past"
      ]
    },
    {
      "form": "known backwards",
      "tags": [
        "participle",
        "past"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "know<,,knew,known> backwards"
      },
      "expansion": "know backwards (third-person singular simple present knows backwards, present participle knowing backwards, simple past knew backwards, past participle known backwards)",
      "name": "en-verb"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "verb",
  "senses": [
    {
      "categories": [
        "British English",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English terms with audio links",
        "English transitive verbs",
        "English verbs",
        "Terms with Danish translations"
      ],
      "glosses": [
        "To have very thorough knowledge of."
      ],
      "links": [
        [
          "thorough",
          "thorough"
        ],
        [
          "knowledge",
          "knowledge"
        ]
      ],
      "raw_glosses": [
        "(UK, transitive) To have very thorough knowledge of."
      ],
      "tags": [
        "UK",
        "transitive"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "LL-Q1860 (eng)-Flame, not lame-know backwards.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/9/94/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/9/94/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav/LL-Q1860_%28eng%29-Flame%2C_not_lame-know_backwards.wav.ogg"
    }
  ],
  "synonyms": [
    {
      "word": "know inside and out"
    },
    {
      "word": "know backward and forward"
    },
    {
      "tags": [
        "US"
      ],
      "word": "know backwards and forwards"
    },
    {
      "tags": [
        "UK",
        "US"
      ],
      "word": "know back to front"
    }
  ],
  "translations": [
    {
      "code": "da",
      "lang": "Danish",
      "sense": "have a very thorough knowledge",
      "word": "have dyb kundskab"
    }
  ],
  "word": "know backwards"
}