That cannot be reproduced or duplicated(adjective)
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Use "irreproducible" in a sentence
"If we were to think of Jobs not as a unique and irreproducible person, but as a mindset, skill set and capacity that could be deconstructed and then modeled, not only could Apple continue its amazing growth, but other companies might follow suit."
"It is also, however, an effective tool for reminding the crowd that they are watching something live and irreproducible."
"Heads would swivel in physiologically irreproducible ways."