Source : Webster's Revised Unabridged Dictionary (1913)

Phrenetic \Phre*net"ic\, Phrenetical \Phre*net"ic*al\, a. [L.
   phreneticus, Gr. ?, ?: cf. F. phr['e]n['e]tique. See
   {Frantic}, and cf. {Frenetic}.]
   Relating to phrenitis; suffering from frenzy; delirious; mad;
   frantic; frenetic. -- {Phre*net"ic*al*ly}, adv.