Adjective: unthinkable ,ún'thing-ku-bul
- Incapable of being conceived or considered
"From earthquakes to hurricanes, tidal waves to terrorist attacks, the unthinkable usually remains the unmentionable"
See also: impossible, inconceivable, incredible, out of the question, unbelievable, unimaginable
Antonym: thinkable
Encyclopedia: Unthinkable