Pronunciation: (pes'tl-unt), [key]
1. producing or tending to produce infectious or contagious, often epidemic, disease; pestilential.
2. destructive to life; deadly; poisonous.
3. injurious to peace, morals, etc.; pernicious.
4. troublesome, annoying, or mischievous.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.