The sound one produces when responding in a sarcastic and or cynic way. Usually used as disagreeing sound or a sound made out of skepticism and or dissaprovment.
Despite the sound having a negative connotation. It can also be used as a sound that agrees.
"Well she ate the last the cookie and didnt offer anyone else one"
"Mmph, she would do that considering how big and selfish she is"
Positive:
"Like all the time she washed the laundry, like all the time she cooks and clean."
(~mm~ff) - descriptive word which relates to the feeling one gets while the alarm clock is ringing on a monday morning after a heavy drunk night out, when that person knows they have to be at work/school in 5 minutes but still wants to sleep more.