impalpable /im-palˈpə-bl/

1. Not perceivable or detectable by touch
2. Not capable of being comprehended or grasped
3. Extremely fine-grained

• river-driver
• river-drivers
• rivered
• riveret
• riverets
• river flat
• riverfront
• riverfronts
• river god
• river gods
• river head
• river heads
• river-hog
• river-hogs
• river horse
• river horses
• riverine
• river-jack
• river-jacks
• river-jack viper
• riverless
• riverlike
• riverman
• rivermen
• river mouth