I have no idea if it is country specific, but in our country if someone doesn't know something he or she would put their lower lip forward.
However, I cannot find a name for this lip gesture. Any help is appreciated.
Learn English – A single word name for the “I don’t know” gesture
gesturessingle-word-requests
Related Solutions
The phrase "verbal shrug" is pretty popular and well established:
In literature, it's often used to describe a sound a speaker has just made, or an emotion captured by his body language, without explicitly identifying the "shrug" in question. So it may be that this set phrase is used precisely because English lacks an established word or term which expresses what a shrug expresses.
I dunno.
The Italians are ahead of us on this one. Boh.
I think the word you're looking for is either ineffable or euphoria (or a combination of both).
INEFFABLE: /ɪnˈɛfəb(ə)l/ too great or extreme to be expressed or described in words.
AND
EUPHORIA: /juːˈfɔːrɪə/ a feeling or state of intense excitement and happiness.
Best Answer
The Gallic shrug includes both the moue (facial gesture) along with the shoulder shrug
"Raise your shoulders; hold up your hands, palms out; stick out your lower lip; raise your eyebrows;"
http://french.about.com/library/weekly/aa020901g.htm