Is there a name for this noise?

I ask the following on behalf of my sister…

You know what when you stick your tongue partway out and go “pppbbtthhhhh” you are “Blowing a raspberry”—right?

SO-
If you place your index finger lightly across your lips, in a horizontal position, and rapidly jiggle it straight up and down while making a noise, you go,“bupitabupitabupitabupita” WHAT IS DOING THAT CALLED???

(I did explain to her that “raspberry” was from the Cockney rhyming slang for “fart.”)

You mean like when someone says: “That guy is totally crazy! Bu-bu-bu-bu-bu-bu-bu, crazy!” ?

I’ve heard it called “bibble”. Sort of like “babble” but I don’t know where I’ve heard that. It had something to do with babies.

Precisely.

Just don’t try Googling with the keywords “fingers on vibrating lips crazy”. It ain’t a result set safe for work, that’s for sure.

Like Swallowed My Cellphone, I’ve seen the noise produced written as “bibble,” but I don’t know of a term for the act itself. “Bibbling”?

Blowing a raspberry is called a linguolabial trill. Maybe we can come up with something using the word “bilabial”.

I’m thinking digitobilabial trill.

I don’t think it’s a trill, because (I think) in a trill, the vibration is caused by air passing over/between the elements – e.g., in the case of the linguolabial trill, the lips and the tongue.

In bibbling (that seems to be the common term for it), the vibration is caused by the finger.

A voiced digitolabial plosive?!??

You’re right, but I don’t think it would be a plosive either-- that does little to describe the outside source of the motion.

Digitolabial click? A ridiculous stretch, but if a click is the result of applying and removing pressure, that’s kinda sorta what the finger does.

Damn, where’s Ezri Dax when I really need her?

The pppllbbbb? That’s pseudoflatulence.

I spent a little time trying to track down “Bibble,” as a mouth noise. Alas, nothing rose to the bait. It’s the name of a software company, and that got in the way. As a slang term, with widely various meanings, it seems to have sprouted from Snoop Dogg’s enigmatic shizzle-talk.

My old 12 pound Webster says *bibble-babble * is idle chat. It says a bibber is a man known to be a drinker, leading me to remember a moment in the movie Amadeus.

*Mozart was at his pool table. He was writing down music, bouncing around a pool ball, and drinking wine. A fellow (Salieri?) comes in to ask if he has finished a piece of music he has promised. Mozart says it’s finished, pointing to his head. “The rest is just scribbling. Scribbling and bibbling, bibbling and scribbling.” * I understood his “bibbling” to mean drinking.