Vibrating Lips

[anaxcrosswords]

No, no, no - it's nothing like that. I'm looking for a word (as a crossword setter I should have it but I honestly have no idea).

There's a sound made when you blow air through your lips and they vibrate against each other. Typically, it's something you do to express boredom or mild frustration. Horses do a similar thing, but obviously not for those reasons!

Is there a name for the action/sound?

[Calibax]

Harrumph? Although that's perhaps more throaty than labial

[mrs.chappie]

Blowing a raspberry?

[bednobs]

raspberry?

[bednobs]

"No, no, no - it's nothing like that"
tht's shame though - actual vibrating lips would be awesome

[slaney]

Bilabial trill?

[anaxcrosswords]

Yeah - harrumph comes more from the throat, while a raspberry uses the tongue. What I'm thinking of just means blowing out through closed lips.

[Negomi]

Siffle or whiffle? To blow or speak with a sibilant sound?

[sandyRoe]

I first thought of humming but as far as suggestions go it's a stinker.

[Negomi]

Horses "nicker” or "whinny" through their lips

[Oldred]

snort ?

[hc4361]

Huff?

[mallyh]

whinney?

[Sipowicz]

Whinny?

[Oldred]

not snort - more nasal

[hc4361]

Pfffft?

[mallyh]

ignore that ...try nickers

[Sipowicz]

Paaarrrppppp?

[sandyRoe]

Wouldn't that be more commonly used to describe a noise from the other end? ^^^ :-))

[sandyRoe]

An onomatopoeic word to describe it. ^^^

[Ann]

How many letters?