It comes from the italian word "bimbominkia" (bimbo => baby; minchione => dumb).
- that sort of teenager who go jumping around, ripping off his/her hair, screaming out loud at the concert of some freak guys who've just got famous thanks to some brand new freak song.
- he thinks he's so cool and skilled surfin' the internet with the father's brand new pc and trying to hack the world with some msn-account-freezing program or some oher stupid cheat.
guy:"That band sucks"
dumbaby: "1ts no tru"
guy: "cmon they cannot play anything"
dumbaby: "1m gonn4 h4ck you"
guy: "you just idiot dumbaby."
/* end of conversation */