1. Naively or unreasonably optimistic
   "I found the article regarding earnings growth slightly Panglossian" 
2. Of or relating to the view that this is the best of all possible worlds

Encyclopedia: Panglossian

• preventable
• preventative
• preventer
• prevention
• preventive
• preventive attack
• preventive medicine
• preventive strike
• preview
• previous
• previous question
• previously
• previse
• prevision
• prevue
• prewar
• prexy
• prey
• prezzie
• Priacanthidae
• Priacanthus
• Priacanthus arenatus
• Priam
• priapic
• priapism