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paradox
noun
°A self-contradictory statement, which can only be true if it is false, and vice versa.
""This sentence is false" is a paradox."
°A counterintuitive conclusion or outcome.
"It is an interesting paradox that drinking a lot of water can often make you feel thirsty."
synonyms: shocker, juxtaposition, contradiction, puzzle more» , quandary, riddle, enigma, koan, reverse psychology