Gone to my uncle's. Uncle's is a pun on the Latin word uncus, a hook. Pawnbrokers employed a hook to lift articles pawned before spouts were adopted. “Gone to the uncus ” is exactly tantamount to the more modern phrase “Up the spout.” The pronoun was inserted to carry out the pun. In French, “C'esl chez ma tante.” At the pawnbroker's.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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