Definition of decrypt in English:



[with object]
  • Make (a coded or unclear message) intelligible.

    ‘the computer can be used to encrypt and decrypt sensitive transmissions’
    • ‘I had a top-secret clearance and would have been part of the team of codebreakers decrypting the message that authorized the use of the ship's nuclear weapons.’
    • ‘Many historians think that a secret Soviet message sent in 1945 (later decrypted by the Venona project) identifies Hiss by a code name.’
    • ‘The Crown supplemented this with an excellent system of opening the mails (and diplomatic pouches, when available) and decrypting messages written in code.’
    • ‘Another thing that will come along - probably after more than a decade or two - is quantum cryptanalysis, where you would use a quantum computer to decrypt existing codes.’
    • ‘An encryption algorithm is a mathematical equation containing the message being encrypted or decrypted.’
    • ‘A Tactical Data Encryption System TDES is a device for storing, encrypting and decrypting messages.’
    • ‘The Aegis system allows a user to encrypt or decrypt a message by just hitting a button and entering a password, and the company says the password part of the process may be phased out soon.’
    • ‘By 1944, over 4,000 German messages were being decrypted daily at Bletchley Park.’
    • ‘Second, when they cannot decrypt the alien code, he gives her the key to the mystery.’
    • ‘Since the eavesdropper doesn't know the starting point, he can't decrypt the message.’
    • ‘It should be easy to encrypt and decrypt messages with the key (which must be kept secret) but difficult to do so without it.’
    • ‘With public key encryption, each person has two keys - a public one that can be disseminated freely which is used to encode messages that can subsequently only be decrypted by the private key.’
    • ‘Failure to comply with a decryption notice will be a criminal office, unless the individual concerned can prove he or she did not have the ability to decrypt the message for any reason, such as losing the password.’
    • ‘Everybody will know the information has come from you because only your public key can decrypt a message that has been encrypted using your private key.’
    • ‘But once you have the right key, it takes less than a fraction of a second to prove that the key is the correct key: All you do is decrypt the message.’
    • ‘During 1942, the US Military Attaché in Cairo, through transmissions decrypted by Italian intelligence, gave him invaluable operational intelligence.’
    • ‘Unlike DVD movies, which are encrypted on the disk and decrypted every time they're played, digital broadcast television has to be unencrypted.’
    • ‘This key would allow the government to decrypt messages as needed, purportedly after seeking and obtaining a warrant.’
    • ‘Several seconds passed before the communication was decrypted and became intelligible.’
    • ‘Otherwise, he can merely decrypt the message without any additional steps or effort.’
    decipher, unravel, untangle, work out, sort out, piece together, solve, interpret, translate, construe, explain, understand, comprehend, apprehend, grasp
    View synonyms


  • A text that has been decoded.

    ‘he passed the raw decrypts to Moscow, but denies that he was a spy’
    • ‘In a semi-polemical preface, he takes some unwarranted shots at post-Cold War studies of Soviet spying that are based on VENONA decrypts and documents from KGB and Comintern archives.’
    • ‘This group was able to keep the secret while getting the sensitive Ultra and Magic decrypts of enemy messages.’
    • ‘Knowledge of the Venona decrypts was actually withheld from President Truman.’
    • ‘Even when Hiss appeared in the Venona decrypts, his supporters refused to believe he was guilty.’
    • ‘Equally, the German Navy passed on decrypts of Allied traffic to Japan after 9 December 1941 only in its own cipher because of suspicions about Anglo-American inroads into Japanese systems.’
    • ‘Indeed, as I write in the book on p. 40, he kept the top-secret decrypts in what he called ‘The Magic Book,’ tucked away in the tightly-guarded Map Room of the White House.’
    • ‘Do you think that the governor of Idaho had access to the MAGIC decrypts, and that he formulated his demand for ‘concentration camps’ on the basis of an evidence-based belief of military necessity?’
    • ‘Only in 1941 did Enigma decrypts pay dividends.’
    • ‘We now know, from the Venona decrypts of Soviet intelligence traffic, that he was guilty as charged of heading a Soviet atomic espionage ring.’
    • ‘Its essence was gross and irresponsible exaggeration of a claim that we now know - from the VENONA decrypts of Soviet cables, among other sources - was true.’
    • ‘But there were still some who challenged her allegations and the validity of the decrypts, calling them forgeries.’
    • ‘A combination of defectors and America's VENONA decrypts caused the collapse of the Soviet networks and the beginning of the end of the era of the ideological agent.’
    • ‘In order to protect the sensitive VENONA project, the decrypts could not be produced as evidence at trial.’


1930s: from de- (expressing reversal) + crypt as in encrypt.