1. A secret method of writing
   "The spies communicated using a cipher that only they could decipher";
   - cypher, cryptograph, secret code
    
2. A message written in a secret code
   "The spies communicated using ciphers";
   - cypher
    
3. A mathematical element that when added to another number yields the same number
   "Adding cipher to any number leaves it unchanged";
   - zero, 0, nought [Brit], cypher, naught [N. Amer]
    
4. No amount at all; absence of any thing, quantity or value
   - nothing, nil, nix [informal], nada [N. Amer, informal], null, aught [archaic], cypher, goose egg [N. Amer, informal], naught [N. Amer], zero, zilch [informal], zip [N. Amer, informal], zippo [N. Amer, informal], nought [Brit]
    
5. A person of no influence
   "He felt like a cipher in the big city";
   - cypher, nobody, nonentity

1. Convert ordinary language into code
   "They ciphered the message before transmitting it";
   - code, encipher, cypher, encrypt, inscribe, write in code
    
2. Make a calculation or computation
   "He ciphered the total in his head";
   - calculate, cypher, compute, work out, reckon, figure [N. Amer]

Derived forms: ciphered, ciphers, ciphering

Type of: code, common person, commoner, digit, encode, figure, message, reason, relative quantity

Encyclopedia: Cipher