PENETRATION n.
The act or process of penetrating, piercing, or entering; also, the act of mentally penetrating into, or comprehending, anything difficult. And to each in ward part, With gentle penetration, though unseen, Shoots invisible virtue even to the deep. Milton. A penetration into the difficulties of algebra. Watts.…
PIERCING 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. -- Pier"cing*ly, adv. -- Pier"cing*ness, n.