1 definition by M. R. Traska

The precise moment when you know a program, band, actor, politician, or other public figure has taken a turn for the worse, gone downhill, become irreversibly bad, is unredeemable, etc.; the moment you realize decay has set in.
Tom Cruise jumped the shark the moment he jumped Oprah's couch.
by M. R. Traska August 28, 2005
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