The term 'Change into Ciphertext' is a process of encoding information so that it can be securely transmitted. The crossword solution for this term is 'ENCODE, ' which is a six-letter word. Encoding is the process of transforming data into a form that is unreadable to anyone who does not have the key to decode it. This is done to protect the data from being accessed by unauthorized individuals. By encoding the data, it is much more difficult for someone to gain access to the information without the proper key.