1. Not capable of being improved on
   - unexcelled, unsurpassed

See also: best

• 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
• deistic
• deity