(Noun):The act of one receiving an angry dragon and the receiver of the angry dragon blowing the load into another womans vagina by sneezing. Bisexuality is a required trait to perform this act.
Bill: Hey bruce you know samantha right?
Bruce: Yeah she's clean as a whistle.
Bill: Not anymore shes not.
Bruce: Why is that?
Bill: Because my girlfriend gave her a dirty whistle last night.
Bruce: HA! that's dirty.
When a person blows in another persons' asshole, thus creating a whistling sound.
Frank gave me a dirty whistle and my ass now tastes like orbit gum. Dirty mouth?