1. Hard to defeat
   "an unbeatable ball team" 
2. Incapable of being overcome or subdued
   - invincible, unvanquishable

See also: unconquerable, unstoppable

• dehydrated
• dehydrated food
• dehydrated foods
• dehydration
• dehydrogenate
• dehydroretinol
• deice
• deicer
• deicide
• deictic
• deictic word
• deific
• deification
• deify
• deign
• Deimos
• deindustrialisation
• deindustrialization
• deinocheirus
• deinonychus
• deionise
• deionize
• deipnosophist
• deism
• deist