1. Not open to challenge
   "unchallengeable facts"; "a position of unchallengeable supremacy"

See also: noncontroversial, uncontroversial

• junk DNA
• junk e-mail
• junk food
• junk heap
• junk mail
• junk pile
• junk shop
• Junker
• Junkers
• junket
• junketeer
• junketing
• junkie
• junky
• junkyard
• Juno
• Junoesque
• junta
• junto
• jupati
• jupati palm
• jupaty
• Jupiter
• Jupiter Fidius
• Jupiter Fulgur