Either bringing bad luck upon yourself or others by mentioning how well things are going.

Brought to public attention during the 1980s in Australia by motor racing legend Dick Johnson who asked commentators not to place the curse on him by mentioning how well he was going in a race.
Commentator: Dick, everything is going well for you in the race today.
Dick: Don't you place the curse of the black jelly bean upon me!
by southcoastreg January 25, 2012
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