"à blanc" meaning in French

{
  "head_templates": [
    {
      "args": {},
      "expansion": "à blanc",
      "name": "fr-prep phrase"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "prep_phrase",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "fr",
          "name": "Firearms",
          "orig": "fr:Firearms",
          "parents": [
            "Weapons",
            "Hunting",
            "Military",
            "Tools",
            "Human activity",
            "Society",
            "Technology",
            "Human behaviour",
            "All topics",
            "Human",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "english": "to shoot blanks",
          "text": "tirer à blanc",
          "type": "example"
        },
        {
          "english": "blank (cartridge)",
          "text": "une balle à blanc",
          "type": "example"
        }
      ],
      "glosses": [
        "blank"
      ],
      "id": "en-à_blanc-fr-prep_phrase-~3HPdKuz",
      "links": [
        [
          "blank",
          "blank"
        ]
      ],
      "qualifier": "armament",
      "raw_glosses": [
        "(armament) blank"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/a blɑ̃/"
    },
    {
      "audio": "LL-Q150 (fra)-Lepticed7-à blanc.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1d/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1d/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav.ogg"
    }
  ],
  "word": "à blanc"
}

{
  "head_templates": [
    {
      "args": {},
      "expansion": "à blanc",
      "name": "fr-prep phrase"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "prep_phrase",
  "senses": [
    {
      "categories": [
        "French entries with incorrect language header",
        "French lemmas",
        "French multiword terms",
        "French prepositional phrases",
        "French terms with IPA pronunciation",
        "French terms with usage examples",
        "Pages with 1 entry",
        "Pages with entries",
        "fr:Firearms"
      ],
      "examples": [
        {
          "english": "to shoot blanks",
          "text": "tirer à blanc",
          "type": "example"
        },
        {
          "english": "blank (cartridge)",
          "text": "une balle à blanc",
          "type": "example"
        }
      ],
      "glosses": [
        "blank"
      ],
      "links": [
        [
          "blank",
          "blank"
        ]
      ],
      "qualifier": "armament",
      "raw_glosses": [
        "(armament) blank"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/a blɑ̃/"
    },
    {
      "audio": "LL-Q150 (fra)-Lepticed7-à blanc.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1d/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1d/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav/LL-Q150_%28fra%29-Lepticed7-%C3%A0_blanc.wav.ogg"
    }
  ],
  "word": "à blanc"
}