Nitwit (noun)

A foolish or stupid person; a simpleton.

Origin:

The word nitwit is derived from the word "nit" meaning "small particle" and "wit" meaning "intelligence" or "intelligence of a person".

Examples:

1. He"s a nitwit who can"t even tie his own shoes.
2. She"s a real nitwit, she can"t find her way home.
3. The company hired a nitwit as a consultant, who had no idea what he was doing.
4. The new recruit was a nitwit, who didn't know how to work the computer.
5. He"s a nitwit, who can"t even make a simple decision.