cryptovirus UK /ˈkɹɪptəʊˌvaɪɹəs/US /ˈkɹɪptoʊˌvaɪɹəs/ noun2 •A type of malware that is used for extortion by encrypting user files and asking for payment in exchange for the decryption key. •A kind of plant virus associated with latent infection of the host, and not transmissible by many means. formscryptoviruses