key date

plural key dates

Definition of key date

: a coin that is the rarest or otherwise most difficult of its series to obtain The 1909-S wheat penny is considered a key date by collectors.

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First Known Use of key date

1976, in the meaning defined above

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The first known use of key date was in 1976

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Cite this Entry

“Key date.” Dictionary, Merriam-Webster, Accessed 25 Nov. 2020.

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