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

See also: epidemic, noxious, pestilence

• burb
• Burbage
• Burbank
• Burberry
• burble
• burbling
• botch
• botch up
• botched
• botcher
• botchy
• botfly
• both
• bother
• botheration
• bothered
• bothersome
• Bothidae
• Bothrops
• Bothrops atrops
• bothy
• botnet
• botonnée
• botonée
• Botox