(also cy·pher ) / ˈsaɪfə(r); NAmE / noun
1.
[ U , C ] a secret way of writing, especially one in which a set of letters or symbols is used to represent others
SYN code :
a message in cipher
—see also decipher
2.
[ C ] ( formal , disapproving ) a person or thing of no importance
3.
( BrE ) the first letters of sb's name combined in a design and used to mark things
••
WORD ORIGIN
late Middle English (in the senses symbol for zero and Arabic numeral ): from Old French cifre , based on Arabic ṣifr zero.