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

See also: unsupported

• beastly
• beat
• beat a dead horse
• beat a retreat
• beat about
• beat about the bush
• beat around the bush
• beat back
• beat down
• beat generation
• beat hollow
• beat in
• beat it
• beat out
• atrazine
• atremble
• atresia
• Atreus
• atrial
• atrial artery
• atrial auricle
• atrial fibrillation
• atrial septal defect
• Atrichornis
• Atrichornithidae