Superlative form of unlucky: most unlucky.(adjective)
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Use "unluckiest" in a sentence
"Now that he is going to keep going on the strength of that story weakens and replacing it with another sub plot turns him into another Diehard type character aka the unluckiest guy on earth."
"He had shot about half of his role at the time of his death so the Time Bandits and Twelve Monkeys is regularly described as the unluckiest movies are frequently beset by problems and, occasionally,"
"MC: I suppose it could mean we're the unluckiest beings on the planet, since our particular set of biological adaptations has resulted in the developmental of a nervous system capable of self-aware thought, which is now able to recognize with full, stark, staring horror the awfulness of our situation, cosmically and ontologically speaking."