The word lollipop was first attested as lolly-pop (describing confections in general) in an eighteenth-century article in the London Chronicle, and there are multiple theories as to what its etymology is. One explanation is that it was borrowed from the Romani word lollipobbul, which meant "candy apple", but there isn't a lot of evidence supporting this. Alternatively, in some northern dialects of England, lolly meant "tongue" (from loll, "to dangle the tongue", from Middle Dutch lollen, "mumble". The pop part would suggest the tongue popping out to lick the candy. I looked up whether the word lollapalooza was related in any way, but it seems that was purely a fanciful formation from the turn of the twentieth century (other early forms included lollypaloozer, lallapaloosa, and lallapalootza).
Hello! I'm Adam Aleksic, a sophomore studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy politics, vexillology, geography, board games, conlanging, and law.