one-time pad


: a random-number additive or mixed keying sequence to be used for a single coded message and then destroyed

Word History


probably from its original form's being a pad of keys whose sheets were torn off and discarded after a single use

First Known Use

1953, in the meaning defined above

Time Traveler
The first known use of one-time pad was in 1953

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Dictionary Entries Near one-time pad

Cite this Entry

“One-time pad.” Dictionary, Merriam-Webster, Accessed 26 Sep. 2023.

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