A word used to portray not believeing something. Its mainly used by 'weeeeeell comun' englishgirls. Think Vicky Pollard. Its often shortened to 'OMGDAAAAAAAAA!!!!' for use on the PC/text etc
"Ohmagodaaaaaaaaaaaaa! No wayrich did you in an alley! That dude is bare buffting and was sooooooo gonna have ME at Rambos party!"