Geusdism \Geusd"ism\ (g[e^]d"[i^]z'm), prop. n. The Marxian socialism and programme of reform through revolution as advocated by the French political leader Jules Basile Guesde (pron. g[e^]d) (1845- ). -- {Guesd"ist}, n. & a. [Webster 1913 Suppl.]