"au" meaning in French

{
  "head_templates": [
    {
      "args": {
        "1": "fr",
        "2": "contraction",
        "3": "used with a singular masculine noun"
      },
      "expansion": "au (used with a singular masculine noun)",
      "name": "head"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "contraction",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "to the, for the, at the",
          "word": "à le"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "French articles",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
        },
        {
          "kind": "other",
          "name": "French prepositions",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 54 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
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          "parents": [],
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        }
      ],
      "examples": [
        {
          "english": "He studies music at the conservatory.",
          "text": "Il étudie la musique au conservatoire.",
          "type": "example"
        }
      ],
      "glosses": [
        "Contraction of à le (“to the, for the, at the”)."
      ],
      "id": "en-au-fr-contraction-0J2jJalF",
      "links": [
        [
          "à",
          "à#French"
        ],
        [
          "le",
          "le#French"
        ]
      ],
      "related": [
        {
          "word": "à la"
        },
        {
          "word": "à l’"
        },
        {
          "word": "aux"
        }
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "contraction"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/o/"
    },
    {
      "audio": "Fr-au.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/4/48/Fr-au.ogg/Fr-au.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/4/48/Fr-au.ogg"
    },
    {
      "rhymes": "-o"
    },
    {
      "homophone": "aulx"
    },
    {
      "homophone": "aux"
    },
    {
      "homophone": "eau"
    },
    {
      "homophone": "eaux"
    },
    {
      "homophone": "haut"
    },
    {
      "homophone": "hauts"
    },
    {
      "homophone": "ho"
    },
    {
      "homophone": "o"
    },
    {
      "homophone": "ô"
    },
    {
      "homophone": "oh"
    },
    {
      "homophone": "os"
    }
  ],
  "word": "au"
}

{
  "head_templates": [
    {
      "args": {
        "1": "fr",
        "2": "contraction",
        "3": "used with a singular masculine noun"
      },
      "expansion": "au (used with a singular masculine noun)",
      "name": "head"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "contraction",
  "related": [
    {
      "word": "à la"
    },
    {
      "word": "à l’"
    },
    {
      "word": "aux"
    }
  ],
  "senses": [
    {
      "alt_of": [
        {
          "extra": "to the, for the, at the",
          "word": "à le"
        }
      ],
      "categories": [
        "French 1-syllable words",
        "French articles",
        "French contractions",
        "French entries with incorrect language header",
        "French non-lemma forms",
        "French prepositions",
        "French terms with IPA pronunciation",
        "French terms with homophones",
        "French terms with usage examples",
        "Pages with 54 entries",
        "Pages with entries",
        "Rhymes:French/o",
        "Rhymes:French/o/1 syllable"
      ],
      "examples": [
        {
          "english": "He studies music at the conservatory.",
          "text": "Il étudie la musique au conservatoire.",
          "type": "example"
        }
      ],
      "glosses": [
        "Contraction of à le (“to the, for the, at the”)."
      ],
      "links": [
        [
          "à",
          "à#French"
        ],
        [
          "le",
          "le#French"
        ]
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "contraction"
      ]
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  ],
  "sounds": [
    {
      "ipa": "/o/"
    },
    {
      "audio": "Fr-au.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/4/48/Fr-au.ogg/Fr-au.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/4/48/Fr-au.ogg"
    },
    {
      "rhymes": "-o"
    },
    {
      "homophone": "aulx"
    },
    {
      "homophone": "aux"
    },
    {
      "homophone": "eau"
    },
    {
      "homophone": "eaux"
    },
    {
      "homophone": "haut"
    },
    {
      "homophone": "hauts"
    },
    {
      "homophone": "ho"
    },
    {
      "homophone": "o"
    },
    {
      "homophone": "ô"
    },
    {
      "homophone": "oh"
    },
    {
      "homophone": "os"
    }
  ],
  "word": "au"
}

{
  "called_from": "form_descriptions/1698",
  "msg": "unrecognized head form: used with a singular masculine noun",
  "path": [
    "au"
  ],
  "section": "French",
  "subsection": "contraction",
  "title": "au",
  "trace": ""
}