1. Exceedingly harmful
   - baneful, deadly, pernicious 
2. Likely to spread and cause an epidemic disease
   - pestilential, pestiferous, plaguey

See also: epidemic, noxious, pestilence

• porcelainize
• porcellaneous
• Porcellio
• Porcellionidae
• porch
• porcine
• porcino
• porcupine
• porcupine ball
• porcupine provision
• porcupinefish
• porcupines
• pore
• pore fungus
• pore mushroom
• porgy
• Porifera
• poriferan
• poriferous
• poring over
• pork
• pork and beans
• pork barrel
• pork belly
• pork butcher