function: [16] The ultimate source of function is the Latin verb fungī ‘perform, discharge’, which may be related to Sanskrit bhunkte ‘he enjoys’. From its past participle, functus, was formed the abstract noun functiō ‘performance, activity’, which passed into English via Old French fonction. Other English derivatives of fungī include defunct and perfunctory [16], etymologically ‘done only to discharge an obligation’. => defunct, perfunctory