We've all done it. Stuck our fingers in our ears and yelled "la-la-la, I can't hear you" whenever a friend tried to spoil a movie or something. Turns out that this form of babble is universal, and definitely has some connotations in the world of linguistics, though we're not sure which. These kinds of sounds are called canonical babbling, and are imitative in nature, so there's no real etymology to it, but hear it gets interesting: In Sanskrit, lalalla was a form of making fun of stammering. In Greek, lalage means "to babble". The English word lullaby is from the Dutch word lullen, which is onomatopoeic for"mumbling or talking nonsense". In Latin, the word lallere also meant "lullaby" and also was probably onomatopoeic (and these lullaby words are characteristic of babbling, because when one is singing to a baby, one does not always adhere to linguistic structures). In Lithuanian, laluoti means "to stammer", and in German, lallen also means "to stammer". All these variations of la meaning similar things are indicative of a common language which precedes all others. Either that or it seconds Chomsky's theory of universal grammar. Man, we know very little about all this stuff, but it's fascinating.
Adam Aleksic, a freshman studying linguistics at Harvard University, has been described as the internet's sixth most famous etymologist. He has disturbing interests in words, vexillology, geography, board games, limericks, and law, and he loves writing about himself in the third person.
The Etymology Nerd