1. Without a basis in reason or fact
   "unfounded suspicions"
   - baseless, groundless, idle, unwarranted, wild

See also: unsupported

• -ess
• -ette
• -ferous
• -graphy
• -hedron
• -ible
• -iferous
• -ise
• -ish
• -ize
• -meister
• -metry
• -nomy
• -oholic
• -onym
• -opia
• -osis
• -pathy
• -phile
• -philiac
• -philous
• -phobe
• -phore
• -phyte
• -plast