When playing pub trivia or pub quiz, a triviawhack is when only one person on a team knows the answer to a particular question, and that answer turns out to be correct. Triviawhacks (or t-whacks) are an indicator of a person's contribution to the team, since without the particular person, the team's aggregate score would be lower by the number of t-whacks they had.

Coined by a group of trivia afficianados in the Southernmost city of the US, Key West Florida.
Fred made the difference in our victory tonight with two triviawhacks. He was the only one on our team who knew that "The Big Sleep" was based on a book by Raymond Chandler.
by Key West Bob April 29, 2019
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