1960, in the meaning defined above
borrowed from French opéron, from opérer "to bring about, effect" (going back to Middle French, borrowed from Late Latin operārī "to work, be efficacious") + -on -on entry 2 — more at operate
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Cite this Entry
“Operon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/operon. Accessed 27 Nov. 2021.
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