Milking a telegram. A telegram is said to be “milked” when the message sent to a specific party is surreptitiously made use of by others.
“They receive their telegrams in cipher to avoid the risk of their being `milked' by rival journals,” —The Times, August 14th, 1869.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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