The Jargon File (version 4.4.7, 29 Dec 2003):

pubic directory
 /pyoob'ik d@·rek´t@·ree/, n.

    [NYU] (also pube directory /pyoob' d@·rek't@·ree/) The pub (public)
    directory on a machine that allows FTP access. So called because it is the
    default location for SEX (sense 1). “I'll have the source in the pube
    directory by Friday.”