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

See also: noncontroversial, uncontroversial

• shadowgraph
• shadowiness
• shadowing
• shadowless
• shadowy
• shaduf
• shady
• shaft
• shaft louse
• shaft of light
• shag
• shag rug
• shagbark
• shagbark hickory
• shagged
• shagged out
• shaggily
• shagginess
• shaggy
• shaggy cap
• shaggy dog story
• shaggy-coated
• shaggy-haired
• shaggymane
• shaggymane mushroom