What does cryptology mean?
Cryptology is the scientific study of secure communication through codes and ciphers. The word covers two complementary branches: cryptography, which concerns the design of systems for encoding messages so only intended recipients can read them, and cryptanalysis, which concerns breaking such systems to read messages without authorisation. Cryptology is a formal, technical term used mainly in academic, military, intelligence, and cybersecurity contexts; in everyday speech, people tend to use narrower terms like 'encryption' or 'codebreaking' instead. Its importance has grown enormously in the digital age, since nearly all modern internet security — from banking to messaging to password protection — rests on cryptographic principles. A specialist in the field is called a cryptologist. Because it is almost always treated as an uncountable noun, it rarely takes a plural form. Understanding cryptology means understanding both how secrets are kept and how they are revealed.
nounThe study or science of codes and ciphers, encompassing both cryptography (creating secure communication systems) and cryptanalysis (breaking them).
- The scientific study of secure communication, including both the creation of codes and ciphers (cryptography) and their breaking (cryptanalysis).
"Modern cryptology underpins everything from online banking to encrypted messaging apps."
"During the Second World War, Alan Turing made landmark contributions to British cryptology."
"She studied cryptology at university before joining a cybersecurity firm."
Cryptology is almost always used as an uncountable noun; a plural form is not established in standard English and should generally be avoided.
"Different national traditions of cryptologies developed during the war. (non-standard)"
Every time you send a WhatsApp message, you're using cryptology refined over 4,000 years of secret-keeping.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of cryptology
Cryptology derives from the Greek roots 'kryptos', meaning hidden or concealed, and 'logia', meaning study of, giving it the literal sense 'the study of hidden things'. These roots were combined in modern usage to name this field of study, alongside related terms like cryptography ('secret writing') and cryptanalysis. Words sharing the same Greek root include cryptic, encrypt, cryptogram, and even the architectural term crypt, referring to an underground chamber.
Related word forms
How cryptology is actually used
Cryptology is an academic and technical term; in everyday conversation people are more likely to say 'encryption' or 'codebreaking'. It is used almost exclusively as a mass (uncountable) noun.
Easily confused with cryptology
Cryptography refers specifically to creating and designing codes and ciphers, while cryptology is the broader umbrella term that also includes cryptanalysis — the breaking of those codes.