"danger-signal" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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          "word": "danger signal"
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          "ref": "1899, Edmund Selous, An Observational Diary of the Habits of Nightjars, The Zoologist, 4th series, vol 3, page 505:",
          "text": "The \"chook chook chook,\" being, I think, the danger-signal to the young, to hide themselves[…]",
          "type": "quote"
        }
      ],
      "glosses": [
        "Alternative spelling of danger signal."
      ],
      "id": "en-danger-signal-en-noun-f9tHbilr",
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  "word": "danger-signal"
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      "form": "danger-signals",
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      "expansion": "danger-signal (plural danger-signals)",
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  "lang_code": "en",
  "pos": "noun",
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      "alt_of": [
        {
          "word": "danger signal"
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          "ref": "1899, Edmund Selous, An Observational Diary of the Habits of Nightjars, The Zoologist, 4th series, vol 3, page 505:",
          "text": "The \"chook chook chook,\" being, I think, the danger-signal to the young, to hide themselves[…]",
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        }
      ],
      "glosses": [
        "Alternative spelling of danger signal."
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  "word": "danger-signal"
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