The Collaborative International Dictionary of English v.0.48:

Piercing \Pier"cing\, a.
   Forcibly entering, or adapted to enter, at or by a point;
   perforating; penetrating; keen; -- used also figuratively;
   as, a piercing instrument, or thrust. "Piercing eloquence."
   --Shak.
   [1913 Webster] -- Pier"cing*ly, adv. -- Pier"cing*ness,
   n.
   [1913 Webster]