cypherpunk Syllabification: (cy·pher·punk)Pronunciation: /ˈsīfərˌpəNGk/Definition of cypherpunk noun a person who uses encryption when accessing a computer network in order to ensure privacy, especially from government authorities. Origin: 1990s: on the pattern of cyberpunkcypherpunk in other Oxford dictionaries Definition of cypherpunk in the British & World English dictionary