periodiccipher
nounUK /ˌpɪəriˈɒdɪk ˈsaɪfə/
US /ˌpɪriˈɑdɪk ˈsaɪfər/
A periodic cipher is a secret code that changes its pattern at set times.
The spy used a periodic cipher that shifted its key every day at noon.
OTHER MEANINGS
2. A cipher whose substitution alphabet repeats after a fixed interval of letters.
The Vigenère cipher is a classic periodic cipher with a repeating keyword.
3. A coding system in which the rule for encoding changes on a regular schedule.
Engineers designed a periodic cipher to rotate keys every hour for security.
4. Any encryption method that cycles through a sequence of transformations.
The device implemented a periodic cipher that looped through five different mappings.