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


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to suppress quietly or indirectly

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