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chicken head: n.

[Commodore] The Commodore Business Machines logo, which strongly resembles a poultry part (within Commodore itself the logo was always called chicken lips). Rendered in ASCII as ‘C=’. With the arguable exception of the Amiga, Commodore's machines were notoriously crocky little bitty boxes, albeit people have written multitasking Unix-like operating systems with TCP/IP networking for them. Thus, this usage may owe something to Philip K. Dick's novel Do Androids Dream of Electric Sheep? (the basis for the movie Blade Runner; the novel is now sold under that title), in which a ‘chickenhead’ is a mutant with below-average intelligence.