An expression of mild contempt or dismissal. Usually made in response upon seeing/hearing nonsense or bullshit. This expression can also used to mask feelings of rejection/hurt to a snub or any other perceived/real social slight.
Dave: I sent a friend invite to Nelson over Facebook and got rejected.
Mike: pfffft. Why do you want to be friends with Nelson for anyway? The guy was basically a total dick to you back in high school.
Dave: Yeah I know, but people change right?
Mike: Dude, get some self-esteem.
A word often used to show disbelief, often used as an example of 'Onomatopoeia'. Also implies 'nobody cares'.
Person: I have a pet tiger. I'm rich. I'm GAWDD DANGG AWESOME. :P oxoxoxoxx
Me: Pfffft. -.-
1 ...a lotta hot air
2 ...that look that some people give you sometimes...hands, on hips, toe tapping, waiting, sighing
3...that whew after sex kinda thing
"Check out my girl over there. She's pissed at me for Lord knows what. Forget her. Pfffft."