penetrating

adj.

[1]	incisive , acute , discriminating , trenchant , keen , incisive , keen , searching , deep , knifelike , penetrative , acute , sharp , piercing , sharp , perceptive , perspicuous , percipient , quick , discriminating , intelligent , sensitive , clever , smart , discerning
[2]	piercing , penetrative , shrill , strident , ear-splitting , ear-shattering , pervasive , pungent , harsh , biting , mordant , strong , stinging