Meaning

1 senses
  1. (Commonwealth, Ireland, UK, idiomatic, informal, not comparable)Very cold.

    Blimey, it's brass monkeys out there today.

Origin

From the phrase cold enough to freeze the balls off a brass monkey - supposedly a referenc

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).

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See also

neighbours in the dictionary
brass monkeys — meaning, examples, forms, synonyms | Krumeto