know-all

know-all
    n 1: someone who thinks he knows everything and refuses to
         accept advice or information from others [syn: {know-it-
         all}, {know-all}]
    

Know-all \Know"-all`\, n.
   One who knows everything; hence, one who makes pretension to
   great knowledge; a wiseacre; a know-it-all; -- usually
   ironical. [Colloq. or R.]
   [1913 Webster]