A game or activity where one player makes up the rules, can change the rules at any time, and doesn't have to tell you the rules (unless you break a rule, of course).
by JusticeCalvin June 30, 2022
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game in which there is only one rule, that being "you cannot repeat any action."
"Baseball is so organized. We should go play Calvinball!"
"Nothing is less organized than Calvinball."
by Lionél Dripps April 15, 2004
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