s]
| 1. | causing insidious harm or ruin; ruinous; injurious; hurtful: pernicious teachings; a pernicious lie. |
| 2. | deadly; fatal: a pernicious disease. |
| 3. | Obsolete. evil; wicked. |

pernicious per·ni·cious (pər-nĭsh'əs)
adj.
Tending to cause death or serious injury; deadly.