Definitions

1. noun

a person or thing that can be identified or understood only with difficulty, or a person who is very difficult to understand; a person or thing that is very hard to understand or explain.

“He was a bit of a cypher on the first day of class.”

2. verb

to conceal or disguise the meaning of something, especially to make it difficult to understand; to make a secret code or message.

“She tried to cypher the password.”

3. verb

to decode or decipher a message or code.

“He spent hours trying to cypher the ancient text.”

4. verb

to substitute for something, especially a letter in a word.

“She had to cypher the missing letter in the crossword.”