magic number

noun

Definition of magic number

1 : one of a set of numbers for which an atomic nucleus exhibits a high degree of stability when either the proton or neutron count is equal to the number
2 : a number that represents a combination of wins for a leader (such as in a baseball pennant race) and losses for a contender which mathematically guarantees the leader's winning the championship

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First Known Use of magic number

1947, in the meaning defined at sense 2

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Time Traveler for magic number

Time Traveler

The first known use of magic number was in 1947

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Dictionary Entries Near magic number

magic music

magic number

magico-religious

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Cite this Entry

“Magic number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/magic%20number. Accessed 16 Jan. 2022.

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