Incredulity (noun)

1. The state of being incredulous; disbelief.
2. The feeling of being skeptical or doubtful about something.

Origin:

From late latin incredulitās, from latin incredulus ("unbelievin.g")

Examples:

1. The audience looked at him with incredulity as he claimed to have flown to the moon.
2. He couldn't hide his incredulity when he heard the news.
3. The lawyer"s incredulity at the defendant"s story was evident in her cross examination.
4. He spoke with a tone of incredulity, as if he could hardly believe what he was hearing.
5. Her incredulity was clear when she heard the proposal for the new project.