Gotta say, I love the word "balderdash." (Though I have a hard time 'hearing' the word without imagining a top-hatted English gentleman huffing it in an upper-crust accent, LOL.) And it has a long history with the English language. =)
Balderdash came into English round about the 1590s, though its origins are misty. Originally it was the name of a drink--a mixture of liquors like milk and beer or beer and wine (eww). It was in the 1670s that it got applied to a senseless jumble of words.
Looking at its parts, it appears that the "balder" is from the Danish word that means "noise, rumble" and the "dash" is from the Scandinavian word, which originally carried the meaning like in dash to pieces. It gained the "move quickly" meaning in the 1300s. So combined, you can see where "balderdash" would come to mean things combined in a noisy, careless fashion.
And of course, now it's a very fun word game. ;-)
I hope everyone has a great week!