1. Impossible to answer
   "an unanswerable argument"

See also: incontestable, incontestible

• solicitously
• solicitousness
• solicitude
• solid
• solid angle
• solid body substance
• solid figure
• solid food
• solid geometry
• solid ground
• solid solution
• solid-colored
• solid-coloured
• solid-hoofed
• solid-state
• solid-state physics
• Solidago
• Solidago bicolor
• Solidago canadensis
• Solidago missouriensis
• Solidago multiradiata
• Solidago nemoralis
• Solidago odora
• Solidago rugosa
• Solidago sempervirens