- jag (n.1)
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- "period of unrestrained activity," 1887, American English, perhaps via intermediate sense of "as much drink as a man can hold" (1670s), from earlier meaning "load of hay or wood" (1590s), of unknown origin. Used in U.S. colloquial speech from 1834 to mean "a quantity, a lot."
- jag (n.2)
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- "slash or rend in a garment," c. 1400, of unknown origin.