How do you spell Penetrating 

Available Definitions:
1)  a. - Having the power of entering, piercing, or pervading; sharp; subtile; penetrative; as, a penetrating odor.
2)  a. - Acute; discerning; sagacious; quick to discover; as, a penetrating mind.
3)  v. t. - To pierce into by the mind; to arrive at the inner contents or meaning of, as of a mysterious or difficult subject; to comprehend; to understand.
4)  v. i. - To pass; to make way; to pierce. Also used figuratively.