(pl. munia) "service performed for the community, duty, work," also "public spectacle paid for by the magistrate, (gladiatorial) entertainment, gift," from Old Latin moenus "service, duty, burden," from PIE *moi-n-es-, generally taken as a suffixed form of base *mei- "to change, go, move;" see mutable
; but Tucker says "more probably" from the other PIE root *mei-
meaning "bind," so that munia = "obligations" and communis = "bound together." A Roman municipum was a city whose citizens had the privileges of Roman citizens but was governed by its own laws.