Cypher (ˈsaɪ fər)

n.

• zero.
• any of the Arabic numerals or figures.
• a person or thing of no value or importance; nonentity.
• a secret method of writing, as by code.
• writing done by such a method; a coded message.
• the key to a secret method of writing.
• a combination of letters, as the initials of a name; monogram

v.i.

• to use figures or numerals arithmetically.
• to write in or as in cipher.

v.t.

• to calculate numerically; figure.
• to convert into cipher; encipher.