Meaning of decoder ring | Babel Free
Definitions
A device consisting of two concentric rings of letters of the alphabet, one of which can be rotated, so as to encode and decode messages according to a simple substitution cipher.
CEFR level
B2
Upper Intermediate
This word is part of the CEFR B2 vocabulary — upper intermediate level.
This word is part of the CEFR B2 vocabulary — upper intermediate level.