1 definition by niecy1026
the act of a man slapping his penis across a person's face (i.e. whipping his penis out on one's face)
Person A: You won't believe what I just saw...?
Person B: What?
Person A: This prostitute was going down on some guy and he just slacktao'd her.
Person B: What?
Person A: This prostitute was going down on some guy and he just slacktao'd her.
by niecy1026 May 25, 2010