"aux trousses" meaning in French

{
  "forms": [
    {
      "form": "aux trousses [+ de ]",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "inv": "1"
      },
      "expansion": "aux trousses (invariable)",
      "name": "fr-adj"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "derived": [
        {
          "word": "le diable aux trousses"
        }
      ],
      "examples": [
        {
          "english": "The police are hot on his heels.",
          "text": "La police est à ses trousses.",
          "type": "example"
        }
      ],
      "glosses": [
        "hot on someone's heels, after (someone)"
      ],
      "id": "en-aux_trousses-fr-adj-4qhc2Tjb",
      "links": [
        [
          "hot on someone's heels",
          "hot on someone's heels"
        ],
        [
          "after",
          "after"
        ]
      ],
      "raw_glosses": [
        "(informal) hot on someone's heels, after (someone)"
      ],
      "related": [
        {
          "word": "coller au train"
        },
        {
          "word": "ne pas lâcher d’une semelle"
        }
      ],
      "tags": [
        "informal",
        "invariable"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/o tʁus/"
    },
    {
      "audio": "LL-Q150 (fra)-LoquaxFR-aux trousses de.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1f/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1f/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav.ogg",
      "text": "Audio"
    }
  ],
  "word": "aux trousses"
}

{
  "derived": [
    {
      "word": "le diable aux trousses"
    }
  ],
  "forms": [
    {
      "form": "aux trousses [+ de ]",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "inv": "1"
      },
      "expansion": "aux trousses (invariable)",
      "name": "fr-adj"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "adj",
  "related": [
    {
      "word": "coller au train"
    },
    {
      "word": "ne pas lâcher d’une semelle"
    }
  ],
  "senses": [
    {
      "categories": [
        "French adjectives",
        "French entries with incorrect language header",
        "French informal terms",
        "French lemmas",
        "French multiword terms",
        "French terms with IPA pronunciation",
        "French terms with audio links",
        "French terms with usage examples"
      ],
      "examples": [
        {
          "english": "The police are hot on his heels.",
          "text": "La police est à ses trousses.",
          "type": "example"
        }
      ],
      "glosses": [
        "hot on someone's heels, after (someone)"
      ],
      "links": [
        [
          "hot on someone's heels",
          "hot on someone's heels"
        ],
        [
          "after",
          "after"
        ]
      ],
      "raw_glosses": [
        "(informal) hot on someone's heels, after (someone)"
      ],
      "tags": [
        "informal",
        "invariable"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/o tʁus/"
    },
    {
      "audio": "LL-Q150 (fra)-LoquaxFR-aux trousses de.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1f/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1f/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav/LL-Q150_%28fra%29-LoquaxFR-aux_trousses_de.wav.ogg",
      "text": "Audio"
    }
  ],
  "word": "aux trousses"
}

{
  "called_from": "form_descriptions/1147",
  "msg": "suspicious related form tags ['canonical']: 'aux trousses [+ de ]' in 'aux trousses (invariable) [+ de (object)]'",
  "path": [
    "aux trousses"
  ],
  "section": "French",
  "subsection": "adjective",
  "title": "aux trousses",
  "trace": ""
}

{
  "called_from": "form_descriptions/1698",
  "msg": "unrecognized head form: object",
  "path": [
    "aux trousses"
  ],
  "section": "French",
  "subsection": "adjective",
  "title": "aux trousses",
  "trace": ""
}