A colloquialism typically validating an outlandish statement to be fact. Often used in Southeast US with y'all at end of statement.
Penny told Rob and Shannon that Sandra was a ho. When Rob appeared skeptical, Penny followed up with "if I'm lying, I'm dying y'all."

Rob later read the bar's bathroom stall which confirmed Penny's statement to be true.
by KY Dude February 25, 2019
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