Main definitions of cipher in US English:

: cipher1cipher2

cipher1

(also cypher)

noun

  • 1A secret or disguised way of writing; a code.

    ‘he was writing cryptic notes in a cipher’
    ‘the information may be given in cipher’
    • ‘Wilkins worked on codes and ciphers, publishing his work in 1641.’
    • ‘Thus unbreakable ciphers do exist, and are not merely a figment of abstract imagination.’
    • ‘I have studied the equation-solving technique for the cryptanalysis of secret-key ciphers.’
    • ‘The first cipher broken was Serpent: the cipher universally considered to be the safest, most conservative choice.’
    • ‘Julius Caesar used a substitution cipher, now known as the Caesar Shift Cipher, where messages were encoded by replacing each letter in the alphabet with the letter three places along.’
    • ‘A cipher is a sort of cryptographic coding system used to disguise information.’
    • ‘It's a computer program that's used to break ciphers, trying to crack the code of the math code.’
    • ‘She was transferred to work on coding and cyphers supervised by Bletchley Park.’
    • ‘One of his most damning accusations is that the agency failed to do what it was mainly designed to do: break high-level ciphers.’
    • ‘Indeed, communication security today, a collective term for all types of codes and ciphers, is probably more important than it has ever been in our history.’
    • ‘British agents broke into the Spanish Embassy in Washington and stole the keys to their ciphers, enabling Bletchley Park to crack the Spanish codes.’
    • ‘The second cipher, which used several different symbols for each English letter in the text, was much more difficult.’
    • ‘The problem with mono-alphabetic ciphers like the Caesar Cipher is that they're relatively easy to crack.’
    • ‘As radio was developed, the ability of the enemy to eavesdrop on radio messages brought about the development of codes and ciphers.’
    • ‘The enciphering and deciphering of messages in secret code or cipher is called cryptology.’
    • ‘He was also an inventor of puzzles, games, ciphers, and mnemonics, and an amateur pioneer in photography.’
    • ‘These cribs were essential for breaking the ciphers.’
    • ‘Encryption, codes and ciphers were once associated only with spies, espionage and illicit letters between lovers.’
    • ‘Other people taught us how to use secret inks, how to use cyphers of course, how to use radio transmitters, and how to use explosives.’
    • ‘A team of researchers in Sweden has cracked the final cipher and claimed the £10,000 prize.’
    code, secret writing
    View synonyms
    1. 1.1 A thing written in a cipher.
      • ‘And why are they targeting me with their runes, signs and ciphers?’
      • ‘The English language uses letters with varying frequencies, allowing code-breakers to calculate which ciphers represent which letters.’
      • ‘An equivalent way of writing the same cipher is shown in the diagram.’
      • ‘He printed ciphers on silk squares so agents could carry the information more easily across borders.’
      • ‘Jim is an expert at classical cryptography and has written a program that is quite good at cracking Enigma cipher.’
      • ‘Japanese culture is a culture in which even written language has evolved from drawings rather than alphabetical ciphers.’
      • ‘Loved ones turn into cyphers, impossible to decode.’
      • ‘In the first century AD, miracles were seen as a secret code - a set of signs and ciphers known only to the Jews.’
      code, secret writing
      View synonyms
    2. 1.2 A key to such a cipher.
      • ‘During this process the cipher secret key is never transmitted on the network.’
      • ‘A Second World War code cipher book won't help!’
      • ‘He was forced to reveal his cipher and to contact headquarters with messages written by his captors.’
  • 2dated A zero; a figure 0.

    • ‘From nine years observations, at Cincinnati, it appears that the thermometer falls below cypher twice every winter.’
    zero, nought, nil, 0
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    1. 2.1 A person or thing of no importance, especially a person who does the bidding of others and seems to have no will of their own.
      • ‘Jim should be the compassionate heart of the film and instead all he is is a cypher, pushed into clichéd situations.’
      • ‘Pablo is not a mere cipher, but a true collaborator.’
      • ‘He will never shed his image as a mere cypher of his father's wealthy friends and the interests of big business.’
      • ‘Fforde's two previous books contain greater emotional depth, and it's disappointing to see his leading lady dwindling into a cypher.’
      • ‘There is a longstanding principle of English parliaments that members are not party ciphers.’
      • ‘Most of the characters rarely develop into something more than ciphers; most remain pawns in the chess game the film is playing with itself.’
      • ‘The characters are not mere ciphers, drawn along by the plot.’
      • ‘She challenges the assumption that actors are mere ciphers channeling the influence of directors and writers.’
      • ‘And we finally get sufficient insight into Connot MacLeod to render him a character rather than a cipher.’
      • ‘This sequel presents us with an almost identical plot and mere ciphers for characters.’
      • ‘Governors have become mere cyphers for the decision-makers - often people with little or no practical experience of the problems faced by prison administrations.’
      • ‘I'm less sympathetic toward Hollywood stars, mostly blank-eyed cyphers with nothing to say and an artless way of expressing it.’
      • ‘He can act as a cypher, a mouthpiece for other's voices.’
      • ‘He would not have got as far as he has if he were the mere unintelligent cipher that he is portrayed as being.’
      • ‘The women seem thinly written, ciphers rather than people, making it difficult for any compelling drama to be sustained.’
      • ‘At times, they resemble mere ciphers who are there to move the story on and no more.’
      • ‘Let us treat our pupils as real people rather than ciphers, and let us encourage their minds to range as far and wide as their talents will allow them.’
      • ‘Astrid throughout remains a mere cipher, a beautiful woman with a crooked smile whom the narrator met while he was a student.’
      • ‘Vassily Gerello, on the other hand, was a total cipher in the title role, and the rest of the cast seemed equally vague.’
      • ‘The behaviour of the contestants has reduced them to little more than cyphers, their actions unsympathetic.’
      nobody, nonentity, nothing, non-person, unimportant person, person of no account
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  • 3A monogram.

    • ‘Her Majesty's wishes were that it should be replaced with a Colour bearing the cypher of the Sovereign of the day.’
    • ‘The badge of the Wiltshire's was a combination of the Maltese Cross and the Duke of Edinburgh's coronet and cipher.’
    • ‘Among the drawings are masterpieces by Rex Whistler, whom the Queen Mother also commissioned to design a new royal cipher.’
    • ‘Of his many personal ciphers and mottoes one appears more frequently on his personal possessions than any other.’
    numeral, number, integer, figure, digit
    View synonyms

verb

  • 1with object Put (a message) into secret writing; encode.

    • ‘The encryption keys are sent over dedicated links, and the messages ciphered with those keys are transmitted over the Internet.’
    • ‘With a black calligraphy pen, each word had been carefully ciphered in a Gothic style.’
    • ‘Theirs took almost five minutes to cypher and decode, ours took one to two minutes.’
    • ‘An ancient diary tells them that the location of a hidden crypt that has been ciphered within the pages of the Renaissance text.’
    • ‘It became a vital tool for the Nazis during World War II who used it to cipher and decipher secret messages.’
  • 2archaic no object Do arithmetic.

    • ‘Many people in the community were illiterate, having little need for education beyond simple ciphering, and how to sign one's name.’

Origin

Late Middle English (in the senses ‘symbol for zero’ and ‘Arabic numeral’): from Old French cifre, based on Arabic ṣifr ‘zero’.

Pronunciation

cipher

/ˈsaɪfər//ˈsīfər/

Main definitions of cipher in US English:

: cipher1cipher2

cipher2

noun

  • A continuous sounding of an organ pipe, caused by a mechanical defect.

verb

[no object]
  • (of an organ pipe) sound continuously.

Origin

Late 18th century: perhaps from cipher.

Pronunciation

cipher

/ˈsaɪfər//ˈsīfər/