jackpot
n.—Gloss: in firefighting slang, a flammable place. «The fire kept trying to creep past them. A few sparks jumped into a nest of wood chips in an old log—”a jackpot,” firefighter lingo for a flammable spot.» —“Few understand Calif. fire fight’s front lines” by Chris Woodyard, William M. Welch, Matt Krantz USA Today Oct. 25, 2007. (source: Double-Tongued Dictionary)
Further reading
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