Thinkable (adjective)

Capable of being thought or imagined.

Origin:

From the verb think + -able.

Examples:

1. It is unthinkable that this would happen.
2. The idea of living on Mars is now thinkable.
3. Some things are just not thinkable for me.
4. It was once unthinkable that humans would travel to space.
5. It is thinkable that the new technology will change the way we live.