| Subject | English | Japanese |
| comp., MS | block cipher | ブロック暗号 (A cipher algorithm that encrypts data in discrete units (called blocks), rather than as a continuous stream of bits. The most common block size is 64 bits. For example, DES is a block cipher) |
| comp., MS | cipher mode | 暗号モード (The method used to encrypt data. The stream cipher mode encodes data one bit at a time. The block cipher mode encodes data one block at a time. Although it tends to execute more slowly than stream cipher, block cipher is more secure) |
| gen. | n cipher text | 暗号文 |
| gen. | n substitution cipher | 換字式暗号 |
| gen. | n transposition cipher | 転置式暗号 |