"brass monkeys" meaning in English

{
  "etymology_text": "From the phrase cold enough to freeze the balls off a brass monkey - supposedly a reference to the brass container for cannon balls on a British man-of-war (but this seems to have been discredited).",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "brass monkeys (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Australian English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "British English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Irish English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "New Zealand English",
          "parents": [],
          "source": "w"
        },
        {
          "_dis": "91 9",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w+disamb"
        },
        {
          "_dis": "93 7",
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
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          "source": "w+disamb"
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        {
          "_dis": "92 8",
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
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          "source": "w+disamb"
        }
      ],
      "examples": [
        {
          "text": "Blimey, it's brass monkeys out there today."
        }
      ],
      "glosses": [
        "very cold"
      ],
      "head_nr": 2,
      "id": "en-brass_monkeys-en-adj-3yzsRG4Z",
      "links": [
        [
          "very",
          "very"
        ],
        [
          "cold",
          "cold"
        ]
      ],
      "raw_glosses": [
        "(British, Ireland, Australia, New Zealand, idiomatic, informal) very cold"
      ],
      "tags": [
        "Australia",
        "British",
        "Ireland",
        "New-Zealand",
        "idiomatic",
        "informal",
        "not-comparable"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-au-brass monkeys.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1b/En-au-brass_monkeys.ogg/En-au-brass_monkeys.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/1/1b/En-au-brass_monkeys.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "wikipedia": [
    "Brass Monkey"
  ],
  "word": "brass monkeys"
}

{
  "etymology_text": "From the phrase cold enough to freeze the balls off a brass monkey - supposedly a reference to the brass container for cannon balls on a British man-of-war (but this seems to have been discredited).",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "noun form"
      },
      "expansion": "brass monkeys",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "_dis": "2 98",
          "kind": "topical",
          "langcode": "en",
          "name": "Temperature",
          "orig": "en:Temperature",
          "parents": [
            "Nature",
            "Weather",
            "All topics",
            "Atmosphere",
            "Fundamental"
          ],
          "source": "w+disamb"
        }
      ],
      "form_of": [
        {
          "word": "brass monkey"
        }
      ],
      "glosses": [
        "plural of brass monkey"
      ],
      "id": "en-brass_monkeys-en-noun-lz6O1Iyy",
      "links": [
        [
          "brass monkey",
          "brass monkey#English"
        ]
      ],
      "tags": [
        "form-of",
        "plural"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-au-brass monkeys.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1b/En-au-brass_monkeys.ogg/En-au-brass_monkeys.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/1/1b/En-au-brass_monkeys.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "word": "brass monkeys"
}

{
  "categories": [
    "English adjectives",
    "English entries with incorrect language header",
    "English entries with topic categories using raw markup",
    "English lemmas",
    "English multiword terms",
    "English non-lemma forms",
    "English noun forms",
    "English terms with audio links",
    "English terms with non-redundant non-automated sortkeys",
    "English uncomparable adjectives",
    "en:Temperature"
  ],
  "etymology_text": "From the phrase cold enough to freeze the balls off a brass monkey - supposedly a reference to the brass container for cannon balls on a British man-of-war (but this seems to have been discredited).",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "brass monkeys (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "Australian English",
        "British English",
        "English idioms",
        "English informal terms",
        "Irish English",
        "New Zealand English"
      ],
      "examples": [
        {
          "text": "Blimey, it's brass monkeys out there today."
        }
      ],
      "glosses": [
        "very cold"
      ],
      "head_nr": 2,
      "links": [
        [
          "very",
          "very"
        ],
        [
          "cold",
          "cold"
        ]
      ],
      "raw_glosses": [
        "(British, Ireland, Australia, New Zealand, idiomatic, informal) very cold"
      ],
      "tags": [
        "Australia",
        "British",
        "Ireland",
        "New-Zealand",
        "idiomatic",
        "informal",
        "not-comparable"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-au-brass monkeys.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1b/En-au-brass_monkeys.ogg/En-au-brass_monkeys.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/1/1b/En-au-brass_monkeys.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "wikipedia": [
    "Brass Monkey"
  ],
  "word": "brass monkeys"
}

{
  "categories": [
    "English adjectives",
    "English entries with incorrect language header",
    "English entries with topic categories using raw markup",
    "English lemmas",
    "English multiword terms",
    "English non-lemma forms",
    "English noun forms",
    "English terms with audio links",
    "English terms with non-redundant non-automated sortkeys",
    "English uncomparable adjectives",
    "en:Temperature"
  ],
  "etymology_text": "From the phrase cold enough to freeze the balls off a brass monkey - supposedly a reference to the brass container for cannon balls on a British man-of-war (but this seems to have been discredited).",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "noun form"
      },
      "expansion": "brass monkeys",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "form_of": [
        {
          "word": "brass monkey"
        }
      ],
      "glosses": [
        "plural of brass monkey"
      ],
      "links": [
        [
          "brass monkey",
          "brass monkey#English"
        ]
      ],
      "tags": [
        "form-of",
        "plural"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "en-au-brass monkeys.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/1/1b/En-au-brass_monkeys.ogg/En-au-brass_monkeys.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/1/1b/En-au-brass_monkeys.ogg",
      "tags": [
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      ],
      "text": "Audio (AU)"
    }
  ],
  "word": "brass monkeys"
}