ciao

Origin

Borrowed from Italian ciao (“hello, goodbye”), from Venetan ciao (“hello, goodbye, your (humble) servant”), from Venetan s-ciao / s-ciavo (“servant, slave”), from Medieval Latin sclavus (“Slav, slave”), related also to Italian schiavo, English Slav, slave and Old Venetan S-ciavón (“Slav”), from Latin Sclavus, ultimately from Proto-Slavic *slověninъ. Not related to Vietnamese chào (“hello, goodbye”). Doublet of Slav and slave.