Proto-IE: *barbar-
Meaning: speaking another language, stranger
Old Indian: barbara- `stammering', m. pl. `barbarians'
Old Greek: bárbaro-s adj./sbst. `Ausländer, ausländisch, Nicht-Grieche, ungriechisch'
Latin: baburrus `stultus, ineptus' [ cf. babit `gauriā(i)', babiger `stultus' ]
Russ. meaning: говорящий не по-нашему