Definition:Cipher


 * Arithmetic:
 * Cipher: An outdated term for the zero digit, especially when used as a placeholder in a number expressed in basis representation form.
 * Cipher: An outdated term for any of the Arabic numerals.
 * Cipher: An archaic term for act of calculation, particularly using the process of algorism.


 * Cryptography:
 * Cipher: An algorithm for converting plaintext into ciphertext.