1. Not easy to believe
   - incredibly, improbably, implausibly 
2. In an unbelievable manner
   "he was unbelievably angry"

See also: unbelievable

Antonym: believably

• parhelion
• pari passu
• pari-mutuel machine
• pariah
• pariah dog
• Paridae
• paries
• parietal
• parietal bone
• parietal cortex
• parietal gyrus
• parietal lobe
• parietal pericardium
• parietal placentation
• parietal pleura
• Parietales
• Parietaria
• Parietaria difussa
• parieto-occipital fissure
• parieto-occipital sulcus
• parietomastoid suture
• parimutuel
• paring
• paring knife
• paripinnate