mid-14c., publishen, "make publicly known, reveal, divulge, announce;" an alteration (by influence of banish, finish, etc.) of publicen (early 14c.), which is from the extended stem of Old French publier "make public, spread abroad, communicate," from Latin publicare "make public," from publicus "public, pertaining to the people" (see public (adj.)).
The meaning "issue (a book, etc.) to the public, cause to be printed and offered for sale or distribution" is from late 14c., also "to disgrace, put to shame; denounce publicly." Related: Published; publishing. In Middle English the verb also meant "to people, populate; to multiply, breed" (late 14c.), for example ben published of "be descended from."