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general::
Also, say uncle. Concede defeat, as in The Serbs want the Bosnians to cry uncle, or If you say uncle right now, I'll let you go first in the next game. This phrase originated about 1900 as an imperative among school-children who would say, "Cry uncle when you've had enough (of a beating)." By the mid-1900s it was being used figuratively, as in the examples.
American Heritage Idioms