Brass monkey (colloquial expression)

The phrase "cold enough to freeze the balls off (or on) a brass monkey" is a colloquial expression used by some English speakers. The reference to the testes (as the term balls is commonly understood to mean) of the brass monkey appears to be a 20th-century variant on the expression, prefigured by a range of references to other body parts, especially the nose and tail.

During the 19th and 20th centuries, small monkeys cast from the alloy brass were very common tourist souvenirs from China and Japan. They usually, but not always, came in a set of three representing the Three Wise Monkeys carved in wood above the Shrine of Toshogu in , , Japan. These monkeys were often cast with all three in a single piece. In other sets they were made singly. Although three was the usual number, some sets of monkeys added a fourth, with its hand covering its genitals. Old brass monkeys of this type are collectors' items.Michael Quinion, advisor to The Oxford English Dictionary and author of the website World Wide Words, writes, "it's more than likely the term came from them".

Early references to "brass monkeys" in the 19th century have no references to balls at all, but instead variously say that it is cold enough to freeze the tail, nose, ears, and whiskers off a brass monkey; or hot enough to "scald the throat" or "singe the hair" of a brass monkey.

The "brass monkey" is the nickname of the house flag of the Cunard Line, adopted in 1878, a lion rampant or on a field gules holding a globe. The reference is almost certainly irreverent humour, rather than a source of the expression, of which variants predate it.

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