1) (n) Any dumb person (usually refers to women unfortunately) who clucks (speaks) alot, and walks around aimlessly or without purpose (like a chicken with its head cut off). "Give me all the chickenheads from Pasadena to Medina, let B.I.G. get in between ya" - Total featuring the B.I.G. (Can't you see ).
2) (n) A derrogatory term used when referring to females who perform oral sex on males, because of the motion of the woman's head: back and forth, like a chickenhead. "Chickenheads be cluckin' in my bedroom" -- Notorious B.I.G. (Warning [??]).
3) (n) Crack addict, because many will perform oral sex to get free crack or money. Repeatedly referred to in "Do or die", a book about the conflict between the Crips and the Bloods in South Central.